diff --git a/lcl/interfaces/win32/win32callback.inc b/lcl/interfaces/win32/win32callback.inc
index f8c4785d51..d668e354bd 100644
--- a/lcl/interfaces/win32/win32callback.inc
+++ b/lcl/interfaces/win32/win32callback.inc
@@ -119,7 +119,7 @@ Var
     PageIndex, Flags: Integer;
     PageHandle: HWND;
   begin
-    Notebook := TObject(GetProp(NotebookHandle, 'Lazarus')) as TCustomNotebook;
+    Notebook := TObject(GetProp(NotebookHandle, 'Wincontrol')) as TCustomNotebook;
     PageIndex := Windows.SendMessage(NotebookHandle, TCM_GETCURSEL, 0, 0);
     PageHandle := Notebook.CustomPage(PageIndex).Handle;
     if Showing then
@@ -243,7 +243,7 @@ Begin
   NotifyUserInput := False;
 
   Assert(False, 'Trace:WindowProc - Getting Object With Callback Procedure');
-  OwnerObject := TObject(GetProp(Window, 'Lazarus'));
+  OwnerObject := TObject(GetProp(Window, 'Wincontrol'));
   Assert(False, 'Trace:WindowProc - Getting Callback Object');
 
   Assert(False, 'Trace:WindowProc - Checking Proc');
@@ -311,7 +311,7 @@ Begin
     End;
     WM_COMMAND:
     Begin
-      OwnerObject := TObject(GetProp(LParam, 'Lazarus'));
+      OwnerObject := TObject(GetProp(LParam, 'Wincontrol'));
       if LParam=0 then OwnerObject := GetMenuItemObject; {menuitem or shortcut}
 
 // is this for speedbuttons?
@@ -347,7 +347,7 @@ Begin
     End;
     WM_CTLCOLORMSGBOX..WM_CTLCOLORSTATIC:
     Begin
-      MsgObject := TObject(GetProp(LParam, 'Lazarus'));
+      MsgObject := TObject(GetProp(LParam, 'WinControl'));
       if MsgObject is TWinControl then
       begin
         Windows.SetTextColor(WParam, ColorToRGB(TWinControl(MsgObject).Font.Color));
@@ -394,7 +394,7 @@ Begin
         if ScrollBar <> 0 then
         begin
           // send message to actual scrollbar window
-          OwnerObject := TObject(Windows.GetProp(ScrollBar, 'Lazarus'));
+          OwnerObject := TObject(Windows.GetProp(ScrollBar, 'Wincontrol'));
         end;
       End;
     End;
@@ -689,7 +689,7 @@ Begin
         if ScrollBar <> 0 then
         begin
           // send message to actual scrollbar window
-          OwnerObject := TObject(Windows.GetProp(ScrollBar, 'Lazarus'));
+          OwnerObject := TObject(Windows.GetProp(ScrollBar, 'Wincontrol'));
         end;
       End;
     End;
@@ -909,6 +909,9 @@ end;
 
 {
   $Log$
+  Revision 1.81  2003/12/27 16:26:55  micha
+  remove redundant window property "lazarus" (from martin)
+
   Revision 1.80  2003/12/26 15:29:33  mattias
   various combobox and other fixes from  Vincent
 
diff --git a/lcl/interfaces/win32/win32object.inc b/lcl/interfaces/win32/win32object.inc
index c9dedf78cc..77a86ec987 100644
--- a/lcl/interfaces/win32/win32object.inc
+++ b/lcl/interfaces/win32/win32object.inc
@@ -2236,9 +2236,6 @@ Begin
         Left, Top, Width, Height, Parent, MenuHandle, HInstance, Nil);
   end;
 
-  if Window <> HWND(nil) then
-    Windows.SetProp(Window, 'Lazarus', Integer(Sender));
-
   If (Sender Is TWinControl) Or (CompStyle = csImage) Then
   Begin
     TWinControl(Sender).Handle := Window;
@@ -2876,7 +2873,6 @@ End;
  ------------------------------------------------------------------------------}
 Procedure TWin32Object.SetOwner(Window: HWND; Owner: TObject);
 Begin
-  SetProp(Window, 'Lazarus', Owner);
   SetProp(Window, 'MsgList', Nil);
 End;
 
@@ -2887,6 +2883,9 @@ End;
 
 {
   $Log$
+  Revision 1.152  2003/12/27 16:26:55  micha
+  remove redundant window property "lazarus" (from martin)
+
   Revision 1.151  2003/12/21 11:51:35  micha
   use oldstyledialog flag
 
diff --git a/lcl/interfaces/win32/win32proc.inc b/lcl/interfaces/win32/win32proc.inc
index af2c4b5d47..08901b161d 100644
--- a/lcl/interfaces/win32/win32proc.inc
+++ b/lcl/interfaces/win32/win32proc.inc
@@ -713,7 +713,7 @@ function GetLCLClientOriginOffset(Handle: HWnd;
 var
   OwnerObject: TObject;
 begin
-  OwnerObject := TObject(GetProp(Handle, 'Lazarus'));
+  OwnerObject := TObject(GetProp(Handle, 'Wincontrol'));
   Result:=GetLCLClientOriginOffset(OwnerObject,LeftOffset,TopOffset);
 end;
 
@@ -748,6 +748,9 @@ End;
  { =============================================================================
 
   $Log$
+  Revision 1.33  2003/12/27 16:26:55  micha
+  remove redundant window property "lazarus" (from martin)
+
   Revision 1.32  2003/12/19 18:18:17  micha
   fix window activation z-order
 
diff --git a/lcl/interfaces/win32/win32winapi.inc b/lcl/interfaces/win32/win32winapi.inc
index 205978cd6f..bf7b41c67e 100644
--- a/lcl/interfaces/win32/win32winapi.inc
+++ b/lcl/interfaces/win32/win32winapi.inc
@@ -1219,7 +1219,7 @@ var
 Begin
   Result := Windows.GetClientRect(Handle, @Rect);
   if not Result then exit;
-  OwnerObject := TObject(GetProp(Handle, 'Lazarus'));
+  OwnerObject := TObject(GetProp(Handle, 'Wincontrol'));
   if OwnerObject is TWinControl then begin
     TheWinControl:=TWinControl(OwnerObject);
     if TheWinControl is TCustomGroupBox then begin
@@ -1880,7 +1880,7 @@ var
 begin
   Result := Windows.GetWindowRect(Handle,@R);
   If (Windows.GetParent(Handle) = 0) then begin
-    OwnerObject := TObject(GetProp(Handle, 'Lazarus'));
+    OwnerObject := TObject(GetProp(Handle, 'Wincontrol'));
     if OwnerObject is TCustomForm then begin
       // the LCL defines the size of a form without the borders.
       // That means for the win32: The client area + menu
@@ -2832,6 +2832,9 @@ end;
 { =============================================================================
 
   $Log$
+  Revision 1.86  2003/12/27 16:26:55  micha
+  remove redundant window property "lazarus" (from martin)
+
   Revision 1.85  2003/12/27 11:03:58  micha
   fix pixmap color (from vincent)