diff -r dee5afe5301f -r 3f74d0d4af4c src/corelib/kernel/qobject.cpp
--- a/src/corelib/kernel/qobject.cpp	Mon Mar 15 12:43:09 2010 +0200
+++ b/src/corelib/kernel/qobject.cpp	Thu Apr 08 14:19:33 2010 +0300
@@ -3264,12 +3264,14 @@
 
             const int method = c->method;
             QObjectPrivate::Sender currentSender;
-            currentSender.sender = sender;
-            currentSender.signal = signal_absolute_index;
-            currentSender.ref = 1;
+            const bool receiverInSameThread = currentThreadData == receiver->d_func()->threadData;
             QObjectPrivate::Sender *previousSender = 0;
-            if (currentThreadData == receiver->d_func()->threadData)
+            if (receiverInSameThread) {
+                currentSender.sender = sender;
+                currentSender.signal = signal_absolute_index;
+                currentSender.ref = 1;
                 previousSender = QObjectPrivate::setCurrentSender(receiver, &currentSender);
+            }
             locker.unlock();
 
             if (qt_signal_spy_callback_set.slot_begin_callback != 0) {
@@ -3285,8 +3287,8 @@
                 metacall(receiver, QMetaObject::InvokeMetaMethod, method, argv ? argv : empty_argv);
             } QT_CATCH(...) {
                 locker.relock();
-
-                QObjectPrivate::resetCurrentSender(receiver, &currentSender, previousSender);
+                if (receiverInSameThread)
+                    QObjectPrivate::resetCurrentSender(receiver, &currentSender, previousSender);
 
                 --connectionLists->inUse;
                 Q_ASSERT(connectionLists->inUse >= 0);
@@ -3301,7 +3303,8 @@
 
             locker.relock();
 
-            QObjectPrivate::resetCurrentSender(receiver, &currentSender, previousSender);
+            if (receiverInSameThread)
+                QObjectPrivate::resetCurrentSender(receiver, &currentSender, previousSender);
 
             if (connectionLists->orphaned)
                 break;