QML Signal with QVariant to C++ Slot is not working in Qt5.3

Are there some changes between Qt5.2 and Qt5.3 regarding to signal and
slots behaviour?

I've tried to switch to Qt5.3 but my Signals and Slots with QVariant are not
working between QML and C++.

I've written a small example that is working fine with Qt5.2 but not with Qt5.3. I get the following error during start-up of the application compiled with Qt5.3:

QObject::connect: No such signal QQuickWindowQmlImpl_QML_0::qmlSignal2(QVariant) in ../railwaycoder-qml_cpp_signal_slots/main.cpp:21

Example is hosted on bitbucket:
Clone URL: https://railwaycoder@bitbucket.org/railwaycoder/qml_cpp_signal_slots.git

I have found out that QVariant Signal is working in Qt5.3 if I change the QML Signal from:

signal qmlSignal2(var anObject)

to:

signal qmlSignal4(variant anObject)

In Qt5.2 both ways are working. Is this a bug or a wanted behaviour in Qt5.3?