diff -pur dbus/dbus/dbus-connection.c dbus.new/dbus/dbus-connection.c
--- dbus/dbus/dbus-connection.c	2006-05-05 18:59:22.000000000 +0300
+++ dbus.new/dbus/dbus-connection.c	2006-09-08 13:32:05.991642496 +0300
@@ -3625,6 +3626,13 @@ dbus_connection_dispatch (DBusConnection
       DBusMessageFilter *filter = link->data;
       DBusList *next = _dbus_list_get_next_link (&filter_list_copy, link);
 
+      if (filter->function == NULL)
+        {
+          _dbus_verbose ("  filter was removed in a callback function\n");
+          link = next;
+          continue;
+        }
+
       _dbus_verbose ("  running filter on message %p\n", message);
       result = (* filter->function) (connection, message, filter->user_data);