Transparent UI flickers on Mac OS X (tested with 10.6)

When a Qt window with Qt::FramelessWindowHint and Qt::WA_TranslucentBackground properties is on top of another application window which updates its window (e.g. A video player, a terminal screen showing a constant flow of output ('find . ') ) . The window flickers and the contents of the other application window bleeds onto it. Also the mouse events are caught by the underlying as if the Qt window doesn't paint itself.

You can build the attached project with Qt Creator and test by putting the application window on top of a terminal window runing the command 'find .' or a youtube video. Just move the mouse over the GUI and see the effect.

Additional info:

Videos demonstrating the glitch has been added.