diff -up metacity-2.25.8/src/core/display.c.stop-spamming-xsession-errors metacity-2.25.8/src/core/display.c

--- metacity-2.25.8/src/core/display.c.stop-spamming-xsession-errors	2008-11-23 00:28:37.000000000 -0500

+++ metacity-2.25.8/src/core/display.c	2008-11-24 21:40:33.000000000 -0500

@@ -3264,10 +3264,12 @@ meta_display_begin_grab_op (MetaDisplay 

   if (display->grab_op != META_GRAB_OP_NONE)

     {

+#if 0

       if (window)

         meta_warning ("Attempt to perform window operation %u on window %s when operation %u on %s already in effect\n",

                       op, window->desc, display->grab_op,

                       display->grab_window ? display->grab_window->desc : "none");

+#endif

       return FALSE;

     }