Index: subsystems/win32/win32k/ntuser/window.c
===================================================================
--- subsystems/win32/win32k/ntuser/window.c	(revision 50902)
+++ subsystems/win32/win32k/ntuser/window.c	(working copy)
@@ -4119,13 +4119,17 @@
       if (GDIOBJ_ValidateHandle(hRgn, GDI_OBJECT_TYPE_REGION))
       {
          hrgnCopy = IntSysCreateRectRgn(0, 0, 0, 0);
+         
+         /* Set public ownership */
+         IntGdiSetRegionOwner(hrgnCopy, GDI_OBJ_HMGR_PUBLIC);
+         
          NtGdiCombineRgn(hrgnCopy, hRgn, 0, RGN_COPY);
       }
       else
          RETURN( 0);
    }
    else
-      hrgnCopy = (HRGN) 1;
+       hrgnCopy = NULL;
 
    if (Window->hrgnClip)
    {