"org.qt-project.qt.mediaplayer" in Qt5 trunk / player-example

The player-example compiled fine but the application starts with the following output:

defaultServiceProvider::requestService(): no service found for - "org.qt-project.qt.mediaplayer"
QMediaPlaylistNavigator: Jump outside playlist range

I checked the following instructions for required libraries:
http://doc.qt.nokia.com/4.7/phonon-overview.html#linux

Those have been installed:

• libgstreamer-plugins-base0.10-0
• libgstreamer-plugins-base0.10-dev
• libgstreamer0.10-0
• libgstreamer0.10-dev

Moreover I tried to modify the example in order to have the QMediaPlayer's availability-check asynchronously. No success either.

Now I ran out of ideas.