diff -pur dbus-glib-0.74/dbus/dbus-gproxy.c dbus-glib-0.74.new/dbus/dbus-gproxy.c
--- dbus-glib-0.74/dbus/dbus-gproxy.c	2007-04-20 19:36:09.000000000 +0300
+++ dbus-glib-0.74.new/dbus/dbus-gproxy.c	2007-10-04 15:24:56.088323208 +0300
@@ -2167,7 +2167,11 @@ dbus_g_proxy_begin_call_internal (DBusGP
                                         timeout))
     goto oom;
   dbus_message_unref (message);
-  g_assert (pending != NULL);
+  if (pending == NULL)
+    {
+      g_error ("Disconnected");
+      return 0;
+    }
 
   call_id = ++priv->call_id_counter;