QSplashScreen hides main window (Ubuntu 12.04)

[imihajlov]

I'd like to use QSplashScreen for my application:
@QApplication a(argc, argv);
QPixmap pixmap("image.png");
QSplashScreen splash(pixmap);
splash.setWindowFlags(splash.windowFlags() | Qt::WindowStaysOnTopHint);
splash.show();
a.processEvents();
MainView *mv(new MainView); // inherits QDeclarativeView
// ...some more initialization here
mv->show();
mv->activateWindow();
splash.finish(mv);

return a.exec();
@

When I use QSplashScreen, the main application window after closing the splashscreen appears active (with focus), but lowered below other windows (even below gnome/unity panels). How can I fix it?

Upd. Qt version is 4.8.1