Mouse double click event is not working properly - fired even when pressing quickly two different buttons one time.

mouseDoubleClickEvent() are fired even when pressing quickly button1 then button2 (or vice versa) while not moving the mouse.
It seem that the problem does not appear if the mouse position changed between the 2 clicks.
I have only tested on Snow Leopard / Cocoa using Qt 4.6.0, but it's possible that the problem impact different versions of Qt / platforms.

I join a test case project.