diff --git a/reactos/include/win32k/ntuser.h b/reactos/include/win32k/ntuser.h
index b5ecb94beba..e8a09ae4ea3 100644
--- a/reactos/include/win32k/ntuser.h
+++ b/reactos/include/win32k/ntuser.h
@@ -179,6 +179,7 @@ NtUserCallNoParam(
 #define ONEPARAM_ROUTINE_GETWINDOWINSTANCE    0x10
 #define ONEPARAM_ROUTINE_SETMESSAGEEXTRAINFO  0x0a
 #define ONEPARAM_ROUTINE_GETCURSORPOSITION    0x0b
+#define ONEPARAM_ROUTINE_ISWINDOWINDESTROY    0x0c
 DWORD
 STDCALL
 NtUserCallOneParam(
diff --git a/reactos/lib/user32/include/user32.h b/reactos/lib/user32/include/user32.h
index 58c8f371286..f948aec80ac 100644
--- a/reactos/lib/user32/include/user32.h
+++ b/reactos/lib/user32/include/user32.h
@@ -90,6 +90,9 @@ void DrawCaret(HWND hWnd, PTHRDCARETINFO CaretInfo);
 #define NtUserGetCursorPos(lpPoint) \
   (BOOL)NtUserCallOneParam((DWORD)lpPoint, ONEPARAM_ROUTINE_GETCURSORPOSITION)
 
+#define NtUserIsWindowInDestroy(hWnd) \
+  (BOOL)NtUserCallOneParam((DWORD)hWnd, ONEPARAM_ROUTINE_ISWINDOWINDESTROY)
+
 LONG WINAPI RegCloseKey(HKEY);
 LONG WINAPI RegOpenKeyExW(HKEY,LPCWSTR,DWORD,REGSAM,PHKEY);
 LONG WINAPI RegQueryValueExW(HKEY,LPCWSTR,LPDWORD,LPDWORD,LPBYTE,LPDWORD);
diff --git a/reactos/lib/user32/misc/stubs.c b/reactos/lib/user32/misc/stubs.c
index 40bc361982e..b8e64d5d590 100644
--- a/reactos/lib/user32/misc/stubs.c
+++ b/reactos/lib/user32/misc/stubs.c
@@ -1,4 +1,4 @@
-/* $Id: stubs.c,v 1.61 2004/05/01 18:06:59 weiden Exp $
+/* $Id: stubs.c,v 1.62 2004/05/02 17:25:20 weiden Exp $
  *
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS user32.dll
@@ -993,15 +993,6 @@ BOOL STDCALL UnregisterUserApiHook(VOID)
   return FALSE;
 }
 
-/*
- * @unimplemented
- */
-BOOL STDCALL IsWindowInDestroy(HWND wnd)
-{
-  UNIMPLEMENTED;
-  return FALSE;
-}
-
 /*
  * @unimplemented
  */
diff --git a/reactos/lib/user32/windows/window.c b/reactos/lib/user32/windows/window.c
index 2e9f12185e9..2e655fc407b 100644
--- a/reactos/lib/user32/windows/window.c
+++ b/reactos/lib/user32/windows/window.c
@@ -1,4 +1,4 @@
-/* $Id: window.c,v 1.114 2004/05/01 18:06:59 weiden Exp $
+/* $Id: window.c,v 1.115 2004/05/02 17:25:21 weiden Exp $
  *
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS user32.dll
@@ -1655,5 +1655,15 @@ AnyPopup(VOID)
   return NtUserAnyPopup();
 }
 
+/*
+ * @implemented
+ */
+BOOL
+STDCALL
+IsWindowInDestroy(HWND hWnd)
+{
+  return NtUserIsWindowInDestroy(hWnd);
+}
+
 /* EOF */
 	 
diff --git a/reactos/subsys/win32k/include/window.h b/reactos/subsys/win32k/include/window.h
index 65a2e06653b..bf218effd2c 100644
--- a/reactos/subsys/win32k/include/window.h
+++ b/reactos/subsys/win32k/include/window.h
@@ -213,6 +213,9 @@ IntGetWindowBorderMeasures(PWINDOW_OBJECT WindowObject, INT *cx, INT *cy);
 BOOL FASTCALL
 IntAnyPopup(VOID);
 
+BOOL FASTCALL
+IntIsWindowInDestroy(PWINDOW_OBJECT Window);
+
 DWORD IntRemoveWndProcHandle(WNDPROC Handle);
 DWORD IntRemoveProcessWndProcHandles(HANDLE ProcessID);
 DWORD IntAddWndProcHandle(WNDPROC WindowProc, BOOL IsUnicode);
diff --git a/reactos/subsys/win32k/ntuser/misc.c b/reactos/subsys/win32k/ntuser/misc.c
index 9bb70ae002f..c2195ccd5b4 100644
--- a/reactos/subsys/win32k/ntuser/misc.c
+++ b/reactos/subsys/win32k/ntuser/misc.c
@@ -1,4 +1,4 @@
-/* $Id: misc.c,v 1.68 2004/05/01 18:06:59 weiden Exp $
+/* $Id: misc.c,v 1.69 2004/05/02 17:25:21 weiden Exp $
  *
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel
@@ -154,18 +154,17 @@ NtUserCallOneParam(
   DWORD Param,
   DWORD Routine)
 {
-  NTSTATUS Status;
-  DWORD Result = 0;
-  PWINSTATION_OBJECT WinStaObject;
-  PWINDOW_OBJECT WindowObject;
-  
   switch(Routine)
   {
     case ONEPARAM_ROUTINE_GETMENU:
+    {
+      PWINDOW_OBJECT WindowObject;
+      DWORD Result;
+      
       WindowObject = IntGetWindowObject((HWND)Param);
       if(!WindowObject)
       {
-        SetLastWin32Error(ERROR_INVALID_HANDLE);
+        SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
         return FALSE;
       }
       
@@ -173,26 +172,36 @@ NtUserCallOneParam(
       
       IntReleaseWindowObject(WindowObject);
       return Result;
+    }
       
     case ONEPARAM_ROUTINE_ISWINDOWUNICODE:
+    {
+      PWINDOW_OBJECT WindowObject;
+      DWORD Result;
+      
       WindowObject = IntGetWindowObject((HWND)Param);
       if(!WindowObject)
       {
-        SetLastWin32Error(ERROR_INVALID_HANDLE);
+        SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
         return FALSE;
       }
       Result = WindowObject->Unicode;
       IntReleaseWindowObject(WindowObject);
       return Result;
+    }
       
     case ONEPARAM_ROUTINE_WINDOWFROMDC:
       return (DWORD)IntWindowFromDC((HDC)Param);
       
     case ONEPARAM_ROUTINE_GETWNDCONTEXTHLPID:
+    {
+      PWINDOW_OBJECT WindowObject;
+      DWORD Result;
+      
       WindowObject = IntGetWindowObject((HWND)Param);
       if(!WindowObject)
       {
-        SetLastWin32Error(ERROR_INVALID_HANDLE);
+        SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
         return FALSE;
       }
       
@@ -200,8 +209,14 @@ NtUserCallOneParam(
       
       IntReleaseWindowObject(WindowObject);
       return Result;
+    }
     
     case ONEPARAM_ROUTINE_SWAPMOUSEBUTTON:
+    {
+      PWINSTATION_OBJECT WinStaObject;
+      NTSTATUS Status;
+      DWORD Result;
+      
       Status = IntValidateWindowStationHandle(PROCESS_WINDOW_STATION(),
                                               KernelMode,
                                               0,
@@ -213,6 +228,7 @@ NtUserCallOneParam(
 
       ObDereferenceObject(WinStaObject);
       return Result;
+    }
     
     case ONEPARAM_ROUTINE_SWITCHCARETSHOWING:
       return (DWORD)IntSwitchCaretShowing((PVOID)Param);
@@ -224,6 +240,10 @@ NtUserCallOneParam(
       return (DWORD)IntEnumClipboardFormats((UINT)Param);
     
     case ONEPARAM_ROUTINE_GETWINDOWINSTANCE:
+    {
+      PWINDOW_OBJECT WindowObject;
+      DWORD Result;
+      
       if(!(WindowObject = IntGetWindowObject((HWND)Param)))
       {
         SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
@@ -233,12 +253,15 @@ NtUserCallOneParam(
       Result = (DWORD)WindowObject->Instance;
       IntReleaseWindowObject(WindowObject);
       return Result;
+    }
     
     case ONEPARAM_ROUTINE_SETMESSAGEEXTRAINFO:
       return (DWORD)MsqSetMessageExtraInfo((LPARAM)Param);
     
     case ONEPARAM_ROUTINE_GETCURSORPOSITION:
     {
+      PWINSTATION_OBJECT WinStaObject;
+      NTSTATUS Status;
       POINT Pos;
       
       if(!Param)
@@ -266,6 +289,24 @@ NtUserCallOneParam(
       
       return (DWORD)TRUE;
     }
+    
+    case ONEPARAM_ROUTINE_ISWINDOWINDESTROY:
+    {
+      PWINDOW_OBJECT WindowObject;
+      DWORD Result;
+      
+      WindowObject = IntGetWindowObject((HWND)Param);
+      if(!WindowObject)
+      {
+        SetLastWin32Error(ERROR_INVALID_WINDOW_HANDLE);
+        return FALSE;
+      }
+      
+      Result = (DWORD)IntIsWindowInDestroy(WindowObject);
+      
+      IntReleaseWindowObject(WindowObject);
+      return Result;
+    }
   }
   DPRINT1("Calling invalid routine number 0x%x in NtUserCallOneParam(), Param=0x%x\n", 
           Routine, Param);
diff --git a/reactos/subsys/win32k/ntuser/window.c b/reactos/subsys/win32k/ntuser/window.c
index 60656074bbd..ae80a000632 100644
--- a/reactos/subsys/win32k/ntuser/window.c
+++ b/reactos/subsys/win32k/ntuser/window.c
@@ -16,7 +16,7 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
-/* $Id: window.c,v 1.222 2004/05/01 18:06:59 weiden Exp $
+/* $Id: window.c,v 1.223 2004/05/02 17:25:21 weiden Exp $
  *
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel
@@ -1100,6 +1100,12 @@ IntAnyPopup(VOID)
   return FALSE;
 }
 
+BOOL FASTCALL
+IntIsWindowInDestroy(PWINDOW_OBJECT Window)
+{
+  return ((Window->Status & WINDOWSTATUS_DESTROYING) == WINDOWSTATUS_DESTROYING);
+}
+
 /* FUNCTIONS *****************************************************************/
 
 /*