Index: /trunk/src/VBox/HostServices/SharedOpenGL/crserverlib/server_window.c
===================================================================
--- /trunk/src/VBox/HostServices/SharedOpenGL/crserverlib/server_window.c	(revision 42516)
+++ /trunk/src/VBox/HostServices/SharedOpenGL/crserverlib/server_window.c	(revision 42517)
@@ -277,4 +277,5 @@
     /* Work-around Intel driver bug */
     CRASSERT(!cr_server.curClient
+            || !cr_server.curClient->currentMural
             || cr_server.curClient->currentMural == mural);
     if (cr_server.curClient && cr_server.curClient->currentMural == mural)