diff -r 89e065397ea6 -r e24348a560a6 src/dbus/qdbusinterface.cpp
--- a/src/dbus/qdbusinterface.cpp	Thu May 27 13:40:48 2010 +0300
+++ b/src/dbus/qdbusinterface.cpp	Fri Jun 11 14:24:45 2010 +0300
@@ -258,7 +258,7 @@
 int QDBusInterface::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
 {
     _id = QDBusAbstractInterface::qt_metacall(_c, _id, _a);
-    if (_id < 0 || !d_func()->isValid)
+    if (_id < 0 || !d_func()->isValid || !d_func()->metaObject)
         return _id;
     return d_func()->metacall(_c, _id, _a);
 }