Index: components/synedit/synedit.pp
===================================================================
--- components/synedit/synedit.pp	(revision 45577)
+++ components/synedit/synedit.pp	(working copy)
@@ -562,6 +562,8 @@
     FOnMouseLink: TSynMouseLinkEvent;
     FPendingFoldState: String;
 
+    FgtkCommit: Boolean;
+
     procedure AquirePrimarySelection;
     function GetChangeStamp: int64;
     function GetCharsInWindow: Integer;
@@ -1131,6 +1133,9 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+  public
+    function gtk_PreeditCommit(const str: PChar; flag: Integer): Boolean;
+       override;
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4010,6 +4015,29 @@
   Result := FMarkupManager.Count;
 end;
 
+// for gtk input method. if return false, key skipped.
+function TCustomSynEdit.gtk_PreeditCommit(const str: PChar; flag: Integer
+  ): Boolean;
+begin
+  Result:=inherited gtk_PreeditCommit(str, flag);
+  if (flag=0) or (flag=2) then
+    FgtkCommit:=flag=0
+    else begin
+      if not fReadOnly then begin
+        if not FgtkCommit then begin
+          // delete on last char
+          if BiDiMode=bdLeftToRight then
+            CommandProcessor(ecSelLeft,'',nil)
+            else
+              CommandProcessor(ecSelRight,'',nil);
+        end;
+        CommandProcessor(ecChar,str,nil);
+        FgtkCommit:=flag=3;
+        Result:=False;
+      end;
+    end;
+end;
+
 procedure TCustomSynEdit.PasteFromClipboard;
 var
   ClipHelper: TSynClipboardStream;
Index: lcl/controls.pp
===================================================================
--- lcl/controls.pp	(revision 45577)
+++ lcl/controls.pp	(working copy)
@@ -1634,6 +1634,10 @@
     property HelpType: THelpType read FHelpType write FHelpType default htContext;
     property HelpKeyword: String read FHelpKeyword write SetHelpKeyword stored IsHelpKeyWordStored;
     property HelpContext: THelpContext read FHelpContext write SetHelpContext stored IsHelpContextStored default 0;
+  //{$ifdef LCLGTK2}
+  public
+    function gtk_PreeditCommit(const str:PChar;flag:Integer):Boolean; virtual;
+  //{$endif}
   end;
 
 
Index: lcl/include/control.inc
===================================================================
--- lcl/include/control.inc	(revision 45577)
+++ lcl/include/control.inc	(working copy)
@@ -5596,7 +5596,18 @@
   Result := UseRightToLeftReading;
 end;
 
+//{$ifdef LCLGTK2}
 {------------------------------------------------------------------------------
+       TControl.gtk_PreeditCommit
+------------------------------------------------------------------------------}
+
+function TControl.gtk_PreeditCommit(const str: PChar; flag: Integer): Boolean;
+begin
+  Result:=True;
+end;
+//{$endif}
+
+{------------------------------------------------------------------------------
        TControl.UseRightToLeftAlignment
 ------------------------------------------------------------------------------}
 
Index: lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lcl/interfaces/gtk2/gtk2globals.pp	(revision 45577)
+++ lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -75,6 +75,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipkey: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -421,6 +423,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipkey:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2proc.inc	(revision 45577)
+++ lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -1990,7 +1990,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2423,7 +2424,12 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_skipkey  then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+              else begin
+                Result:=True;
+                im_context_skipkey:=false;
+              end;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 45577)
+++ lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,67 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TControl;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TControl(GetNearestLCLObject(im_context_widget));
+        im_context_skipkey:=not Control.gtk_PreeditCommit(PChar(im_context_string),3);
+      end;
 end;
 
+//DW
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  Control:TControl;
+begin
+  im_context_use:=True;
+  if (im_context_widget<>nil) and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TControl(GetNearestLCLObject(im_context_widget));
+        im_context_skipkey:=not Control.gtk_PreeditCommit(PChar(''),0);
+      end;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  Control:TControl;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TControl(GetNearestLCLObject(im_context_widget));
+        im_context_skipkey := not Control.gtk_PreeditCommit(PChar(''),2);
+      end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TControl;
+  compostr:string;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    compostr:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    im_context_skipkey:=not control.gtk_PreeditCommit(PChar(compostr),1);
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1041,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin

Index: components/synedit/synedit.pp
===================================================================
--- components/synedit/synedit.pp	(revision 45586)
+++ components/synedit/synedit.pp	(working copy)
@@ -562,6 +562,7 @@
     FOnMouseLink: TSynMouseLinkEvent;
     FPendingFoldState: String;
 
+
     procedure AquirePrimarySelection;
     function GetChangeStamp: int64;
     function GetCharsInWindow: Integer;
@@ -1131,6 +1132,8 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+  protected
+    function DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean; override;
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4010,6 +4013,18 @@
   Result := FMarkupManager.Count;
 end;
 
+function TCustomSynEdit.DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean;
+begin
+  // for gtk input method.
+  if (UTF8Key=#8) and (not ReadOnly) then begin
+    if BiDiMode=bdLeftToRight then
+      CommandProcessor(ecSelLeft,#0,nil)
+      else
+        CommandProcessor(ecSelRight,#0,nil);
+  end;
+  Result:=inherited DoUTF8KeyPress(UTF8Key);
+end;
+
 procedure TCustomSynEdit.PasteFromClipboard;
 var
   ClipHelper: TSynClipboardStream;
Index: lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lcl/interfaces/gtk2/gtk2globals.pp	(revision 45586)
+++ lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -75,6 +75,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipDelete: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -421,6 +423,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipDelete:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2proc.inc	(revision 45586)
+++ lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -1990,7 +1990,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2423,7 +2424,10 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_use then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+            else
+              Result:=True;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 45586)
+++ lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,82 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TWinControl;
+  temp:TUTF8Char;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TWinControl(GetNearestLCLObject(im_context_widget));
+        if not im_context_skipDelete then begin
+          temp:=#8;
+          Control.IntfUTF8KeyPress(temp,1,False);
+        end;
+        temp:=UTF8Copy(im_context_string,1,1);
+        Control.IntfUTF8KeyPress(temp,1,False);
+        im_context_skipDelete:=True;
+      end;
 end;
 
+//DW
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_use:=True;
+    im_context_skipDelete:=True;
+  end else
+    im_context_use:=False;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_skipDelete:=True;
+  end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TWinControl;
+  compostr:string;
+  temp:TUTF8Char;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    compostr:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    if not im_context_skipDelete then begin
+      temp:=#8;
+      control.IntfUTF8KeyPress(temp,1,False);
+    end else
+      im_context_skipDelete:=False;
+    temp:=UTF8Copy(compostr,1,1);
+    control.IntfUTF8KeyPress(temp,1,False);
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1056,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin

Index: components/synedit/synedit.pp
===================================================================
--- components/synedit/synedit.pp	(revision 45588)
+++ components/synedit/synedit.pp	(working copy)
@@ -1131,6 +1131,8 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+  protected
+    function DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean; override;
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4010,6 +4012,14 @@
   Result := FMarkupManager.Count;
 end;
 
+function TCustomSynEdit.DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean;
+begin
+  // for gtk input method.
+  if (UTF8Key=#8) and (not ReadOnly) then
+    CommandProcessor(ecSelLeft,#0,nil);
+  Result:=inherited DoUTF8KeyPress(UTF8Key);
+end;
+
 procedure TCustomSynEdit.PasteFromClipboard;
 var
   ClipHelper: TSynClipboardStream;
Index: lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lcl/interfaces/gtk2/gtk2globals.pp	(revision 45588)
+++ lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -75,6 +75,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipDelete: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -421,6 +423,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipDelete:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2proc.inc	(revision 45588)
+++ lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -1990,7 +1990,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2423,7 +2424,10 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_use then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+            else
+              Result:=True;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 45588)
+++ lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,82 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TWinControl;
+  temp:TUTF8Char;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TWinControl(GetNearestLCLObject(im_context_widget));
+        if not im_context_skipDelete then begin
+          temp:=#8;
+          Control.IntfUTF8KeyPress(temp,1,False);
+        end;
+        temp:=UTF8Copy(im_context_string,1,1);
+        Control.IntfUTF8KeyPress(temp,1,False);
+        im_context_skipDelete:=True;
+      end;
 end;
 
+//DW
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_use:=True;
+    im_context_skipDelete:=True;
+  end else
+    im_context_use:=False;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_skipDelete:=True;
+  end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TWinControl;
+  compostr:string;
+  temp:TUTF8Char;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    compostr:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    if (not im_context_skipDelete) and (Length(compostr)>0) then begin
+      temp:=#8;
+      control.IntfUTF8KeyPress(temp,1,False);
+    end else
+      im_context_skipDelete:=False;
+    temp:=UTF8Copy(compostr,1,1);
+    control.IntfUTF8KeyPress(temp,1,False);
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1056,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin

Index: components/synedit/synedit.pp
===================================================================
--- components/synedit/synedit.pp	(revision 45619)
+++ components/synedit/synedit.pp	(working copy)
@@ -1131,6 +1131,8 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+  protected
+    function DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean; override;
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4010,6 +4012,14 @@
   Result := FMarkupManager.Count;
 end;
 
+function TCustomSynEdit.DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean;
+begin
+  // for gtk input method.
+  if (UTF8Key=#8) and (not ReadOnly) then
+    CommandProcessor(ecSelLeft,#0,nil);
+  Result:=inherited DoUTF8KeyPress(UTF8Key);
+end;
+
 procedure TCustomSynEdit.PasteFromClipboard;
 var
   ClipHelper: TSynClipboardStream;
Index: lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lcl/interfaces/gtk2/gtk2globals.pp	(revision 45619)
+++ lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -78,6 +78,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipDelete: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -424,6 +426,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipDelete:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2proc.inc	(revision 45619)
+++ lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -1990,7 +1990,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2351,7 +2352,7 @@
 
       Msg.KeyData := CommonKeyData or (Flags shl 16) or $0001 {TODO:  repeatcount};
 
-      if not KeyAlreadyHandledByGtk
+      if (not KeyAlreadyHandledByGtk) and (not im_context_use)
       then begin
         // send the (Sys)KeyDown message directly to the LCL
         NotifyApplicationUserInput(TControl(TargetObj), Msg.Msg);
@@ -2423,7 +2424,10 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_use then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+            else
+              Result:=True;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 45619)
+++ lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,82 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TWinControl;
+  temp:TUTF8Char;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TWinControl(GetNearestLCLObject(im_context_widget));
+        if not im_context_skipDelete then begin
+          temp:=#8;
+          Control.IntfUTF8KeyPress(temp,1,False);
+        end;
+        temp:=UTF8Copy(im_context_string,1,1);
+        Control.IntfUTF8KeyPress(temp,1,False);
+        im_context_skipDelete:=True;
+      end;
 end;
 
+//DW
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_use:=True;
+    im_context_skipDelete:=True;
+  end else
+    im_context_use:=False;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_skipDelete:=True;
+  end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TWinControl;
+  compostr:string;
+  temp:TUTF8Char;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    compostr:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    if (not im_context_skipDelete) and (Length(compostr)>0) then begin
+      temp:=#8;
+      control.IntfUTF8KeyPress(temp,1,False);
+    end else
+      im_context_skipDelete:=False;
+    temp:=UTF8Copy(compostr,1,1);
+    control.IntfUTF8KeyPress(temp,1,False);
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1056,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin

Index: components/synedit/synedit.pp
===================================================================
--- components/synedit/synedit.pp	(revision 45786)
+++ components/synedit/synedit.pp	(working copy)
@@ -1131,6 +1131,8 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+  protected
+    function DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean; override;
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4010,6 +4012,14 @@
   Result := FMarkupManager.Count;
 end;
 
+function TCustomSynEdit.DoUTF8KeyPress(var UTF8Key: TUTF8Char): boolean;
+begin
+  // for gtk input method.
+  if (UTF8Key=#8) and (not ReadOnly) then
+    CommandProcessor(ecSelLeft,#0,nil);
+  Result:=inherited DoUTF8KeyPress(UTF8Key);
+end;
+
 procedure TCustomSynEdit.PasteFromClipboard;
 var
   ClipHelper: TSynClipboardStream;
Index: lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lcl/interfaces/gtk2/gtk2globals.pp	(revision 45786)
+++ lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -78,6 +78,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipDelete: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -424,6 +426,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipDelete:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2proc.inc	(revision 45786)
+++ lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -1993,7 +1993,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2000,7 +2001,7 @@
   begin
     Result := false;
     if AWidget = nil then exit;
-    
+
     if GtkWidgetIsA(AWidget, gtk_entry_get_type)
     then begin
       // the gtk_entry handles the following keys
@@ -2354,7 +2355,7 @@
 
       Msg.KeyData := CommonKeyData or (Flags shl 16) or $0001 {TODO:  repeatcount};
 
-      if not KeyAlreadyHandledByGtk
+      if (not KeyAlreadyHandledByGtk) and (not im_context_use)
       then begin
         // send the (Sys)KeyDown message directly to the LCL
         NotifyApplicationUserInput(TControl(TargetObj), Msg.Msg);
@@ -2426,7 +2427,10 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_use then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+            else
+              Result:=True;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 45786)
+++ lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,85 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TWinControl;
+  temp:TUTF8Char;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  { Handle commit string at ending composition,
+    it cannot handled by HandleGTKKeyUpDown }
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TWinControl(GetNearestLCLObject(im_context_widget));
+        if not im_context_skipDelete then begin
+          temp:=#8;
+          Control.IntfUTF8KeyPress(temp,1,False);
+        end;
+        temp:=UTF8Copy(im_context_string,1,1);
+        Control.IntfUTF8KeyPress(temp,1,False);
+        im_context_string:='';
+        im_context_skipDelete:=True;
+      end;
 end;
 
+//DW
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_use:=True;
+    im_context_skipDelete:=True;
+  end else
+    im_context_use:=False;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_skipDelete:=True;
+  end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TWinControl;
+  compostr:string;
+  temp:TUTF8Char;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    compostr:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    if (not im_context_skipDelete) and (Length(compostr)>0) then begin
+      temp:=#8;
+      control.IntfUTF8KeyPress(temp,1,False);
+    end else
+      im_context_skipDelete:=False;
+    temp:=UTF8Copy(compostr,1,1);
+    control.IntfUTF8KeyPress(temp,1,False);
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1059,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin

Index: lazarus/components/synedit/synedit.pp
===================================================================
--- lazarus/components/synedit/synedit.pp	(revision 47587)
+++ lazarus/components/synedit/synedit.pp	(working copy)
@@ -1142,6 +1142,10 @@
     property OnSpecialLineColors: TSpecialLineColorsEvent read FOnSpecialLineColors write SetSpecialLineColors;  deprecated;
     property OnSpecialLineMarkup: TSpecialLineMarkupEvent read FOnSpecialLineMarkup write SetSpecialLineMarkup;
     property OnStatusChange: TStatusChangeEvent read fOnStatusChange write fOnStatusChange;
+{$ifdef LCLGtk2}
+  protected
+    procedure GTK_IMComposition(var Message:TMessage); message LM_IM_COMPOSITION;
+{$endif}
   end;
 
   TSynEdit = class(TCustomSynEdit)
@@ -4029,6 +4033,26 @@
   Result := FMarkupManager.Count;
 end;
 
+{$ifdef LCLGtk2}
+procedure TCustomSynEdit.GTK_IMComposition(var Message: TMessage);
+var
+  IMStr:TUTF8Char;
+begin
+  if (not ReadOnly) then
+  begin
+    // delete previous character by selection
+    if Message.WParam and GTK_IM_FLAG_REPLACE<>0 then
+      CommandProcessor(ecSelLeft,#0,nil);
+    // valid string at composition & commit
+    if Message.WParam and (GTK_IM_FLAG_START or GTK_IM_FLAG_END)=0 then
+    begin
+      IMStr:=pchar(Message.LParam);
+      UTF8KeyPress(IMStr);
+    end;
+  end;
+end;
+{$endif}
+
 procedure TCustomSynEdit.SetCaretTypeSize(AType: TSynCaretType; AWidth, AHeight, AXOffs,
   AYOffs: Integer);
 begin
Index: lazarus/lcl/interfaces/gtk2/gtk2globals.pp
===================================================================
--- lazarus/lcl/interfaces/gtk2/gtk2globals.pp	(revision 47587)
+++ lazarus/lcl/interfaces/gtk2/gtk2globals.pp	(working copy)
@@ -78,6 +78,8 @@
   im_context: PGtkIMContext = nil;
   im_context_widget: PGtkWidget = nil;
   im_context_string: string = '';
+  im_context_use: Boolean = False; //DW
+  im_context_skipDelete: Boolean = False;
 
 procedure ResetDefaultIMContext;
 
@@ -424,6 +426,8 @@
   end;
   im_context_widget:=nil;
   im_context_string:='';
+  im_context_use:=False; //DW
+  im_context_skipDelete:=False;
 end;
 
 procedure AddCharsetEncoding(CharSet: Byte; CharSetReg, CharSetCod: CharSetStr;
Index: lazarus/lcl/interfaces/gtk2/gtk2proc.inc
===================================================================
--- lazarus/lcl/interfaces/gtk2/gtk2proc.inc	(revision 47587)
+++ lazarus/lcl/interfaces/gtk2/gtk2proc.inc	(working copy)
@@ -2000,7 +2000,8 @@
       end;
       Exit;
     end;
-    Result := (AEvent^.Length > 0) or (GetSpecialChar <> #0);
+    //DW
+    Result := ((not im_context_use) and (AEvent^.Length > 0)) or (GetSpecialChar <> #0);
   end;
   
   function KeyAlreadyHandledByGtk: boolean;
@@ -2007,7 +2008,7 @@
   begin
     Result := false;
     if AWidget = nil then exit;
-    
+
     if GtkWidgetIsA(AWidget, gtk_entry_get_type)
     then begin
       // the gtk_entry handles the following keys
@@ -2361,7 +2362,7 @@
 
       Msg.KeyData := CommonKeyData or (Flags shl 16) or $0001 {TODO:  repeatcount};
 
-      if not KeyAlreadyHandledByGtk
+      if (not KeyAlreadyHandledByGtk) and (not im_context_use)
       then begin
         // send the (Sys)KeyDown message directly to the LCL
         NotifyApplicationUserInput(TControl(TargetObj), Msg.Msg);
@@ -2433,7 +2434,10 @@
         begin
           OldCharacter := Character;
           // send the key after navigation keys were handled
-          Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey);
+          if not im_context_use then
+            Result := TWinControl(LCLObject).IntfUTF8KeyPress(Character, 1, SysKey)
+            else
+              Result:=True;
           if Result or (Character = '') then
             // dont' stop key event here, just clear it since we need a keyUp event
             ClearKey
Index: lazarus/lcl/interfaces/gtk2/gtk2widgetset.inc
===================================================================
--- lazarus/lcl/interfaces/gtk2/gtk2widgetset.inc	(revision 47587)
+++ lazarus/lcl/interfaces/gtk2/gtk2widgetset.inc	(working copy)
@@ -216,11 +216,88 @@
 
 procedure gtk_commit_cb ({%H-}context: PGtkIMContext; const Str: Pgchar;
   {%H-}Data: Pointer); cdecl;
+var
+  Control:TWinControl;
+  Flag:WPARAM;
 begin
   //DebugLn(['gtk_commit_cb ',dbgstr(Str),'="',Str,'"']);
   im_context_string:=Str;
+  { Handle commit string at ending composition,
+    it cannot handled by HandleGTKKeyUpDown }
+  if im_context_use and (im_context_widget<>nil) and (im_context_string<>'') and
+     gtk_widget_is_focus(im_context_widget) then
+      begin
+        Control:=TWinControl(GetNearestLCLObject(im_context_widget));
+        Flag:=GTK_IM_FLAG_COMMIT;
+        if not im_context_skipDelete then
+          Flag:=Flag or GTK_IM_FLAG_REPLACE;
+        SendMessage(Control.Handle,LM_IM_COMPOSITION,Flag,LPARAM(pchar(im_context_string)));
+        im_context_string:='';
+        im_context_skipDelete:=True;
+      end;
 end;
 
+procedure gtk_preedit_start_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+  Flag:WPARAM;
+begin
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_use:=True;
+    im_context_skipDelete:=True;
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    Flag:=GTK_IM_FLAG_START;
+    SendMessage(Control.Handle,LM_IM_COMPOSITION,Flag,LPARAM(Data));
+  end else
+    im_context_use:=False;
+end;
+
+procedure gtk_preedit_end_cb({%H-}context: PGtkIMContext; {%H-}Data: Pointer); cdecl;
+var
+  control:TWinControl;
+  Flag:WPARAM;
+begin
+  im_context_use:=False;
+  if (im_context_widget<>nil) and
+     (gtk_widget_is_focus(im_context_widget)) and
+     (GetNearestLCLObject(im_context_widget) is TCustomControl) then
+  begin
+    im_context_skipDelete:=True;
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    Flag:=GTK_IM_FLAG_END;
+    SendMessage(control.Handle,LM_IM_COMPOSITION,Flag,LPARAM(Data));
+  end;
+end;
+
+procedure gtk_preedit_changed_cb({%H-}context:PGtkIMContext; {%H-}Data:Pointer); cdecl;
+var
+  str:Pgchar;
+  pangoattr:PPangoAttrList;
+  pos:gint;
+  control:TWinControl;
+  Flag:WPARAM;
+begin
+  if im_context_use and (im_context_widget<>nil) and
+    gtk_widget_is_focus(im_context_widget) then
+  begin
+    control:=TWinControl(GetNearestLCLObject(im_context_widget));
+    pos:=1;
+    gtk_im_context_get_preedit_string(context,@str,pangoattr,@pos);
+    im_context_string:=str;
+    g_free(str);
+    pango_attr_list_unref(pangoattr);
+    Flag:=GTK_IM_FLAG_COMPOSITION;
+    if (not im_context_skipDelete) and (Length(im_context_string)>0) then begin
+      Flag:=Flag or GTK_IM_FLAG_REPLACE;
+    end else
+      im_context_skipDelete:=False;
+    SendMessage(control.Handle,LM_IM_COMPOSITION,Flag,LPARAM(pchar(im_context_string)));
+  end;
+end;
+
 {$IfNDef GTK2_2}
 procedure gtkTreeSelectionCountSelectedRows({%H-}model : PGtkTreeModel; {%H-}path : PGtkTreePath;
                                   {%H-}iter : PGtkTreeIter; data : PGint); cdecl;
@@ -985,6 +1062,13 @@
   im_context:=gtk_im_multicontext_new;
   g_signal_connect (G_OBJECT (im_context), 'commit',
     G_CALLBACK (@gtk_commit_cb), nil);
+  //DW
+  g_signal_connect (G_OBJECT (im_context), 'preedit-start',
+    G_CALLBACK (@gtk_preedit_start_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-end',
+    G_CALLBACK (@gtk_preedit_end_cb), nil);
+  g_signal_connect (G_OBJECT (im_context), 'preedit-changed',
+    G_CALLBACK (@gtk_preedit_changed_cb), nil);
   {$IFDEF HASX}
   if IsNoTransientWM then
   begin
Index: lazarus/lcl/lmessages.pp
===================================================================
--- lazarus/lcl/lmessages.pp	(revision 47587)
+++ lazarus/lcl/lmessages.pp	(working copy)
@@ -93,7 +93,15 @@
   LM_INTERFACELAST  = LM_LCL + 199;
   
   LM_UNKNOWN        = LM_INTERFACELAST + 1;
+  LM_IM_COMPOSITION = LM_UNKNOWN + 1; // gtk IM
 
+  // GTK IM Flags
+  GTK_IM_FLAG_START       = 1;
+  GTK_IM_FLAG_COMPOSITION = 2;
+  GTK_IM_FLAG_END         = 4;
+  GTK_IM_FLAG_COMMIT      = 8;
+  GTK_IM_FLAG_REPLACE     = 16;
+
   //-------------
   //end of messages that are sent to the interface
   //-------------