diff --git a/graph/win32/grwin32.c b/graph/win32/grwin32.c
index 29a8626195c281bcfeab11e3638ddd988cb08542..431e4c685a6fe4483478e0870713653b39139dcc 100644
--- a/graph/win32/grwin32.c
+++ b/graph/win32/grwin32.c
@@ -446,7 +446,7 @@ DWORD WINAPI Window_ThreadProc( LPVOID lpParameter )
 
   ShowWindow( surface->window, SW_SHOWNORMAL );
 
-  while ( GetMessage( &msg, surface->window, 0, 0 ) > 0 )
+  while ( GetMessage( &msg, NULL, 0, 0 ) > 0 )
   {
     TranslateMessage( &msg );
     DispatchMessage( &msg );