Index: gnome-session/logout.c
===================================================================
--- gnome-session/logout.c.orig
+++ gnome-session/logout.c
@@ -28,6 +28,9 @@
 #include <gtk/gtkinvisible.h>
 #include <gdk/gdkx.h>
 
+#include <X11/Xlib.h>
+#include <X11/Xatom.h>
+
 #include <gconf/gconf-client.h>
 
 #include <libgnomeui/gnome-help.h>
@@ -168,6 +171,10 @@ fadeout_screen (GdkScreen *screen,
   int attr_mask;
   GdkGCValues values;
   FadeoutData *fadeout;
+  GdkAtom property = gdk_atom_intern ("_NET_WM_STATE_DISPLAY_MODAL", FALSE);
+
+  if (gdk_x11_screen_supports_net_wm_hint (screen, property))
+    return;
 
   fadeout = g_new (FadeoutData, 1);