"Application menu" (like Mac) on all plattforms

[Kumula]

Hi there,

after plan A (implementing an application menu as in MacOS, decorated with a nice pixmap) has failed (because of a Qt bug, see http://www.qtcentre.org/forum/showthread.php?t=501), I'm thinking about a plan B. And maybe, this would be easier than a pixmap in the menubar:

So first I ask you if it's possible to make menubar items bold? So that it'll look similar to this:
------------------------------------------------------------------------
Program File Edit View Extras Settings ...
------------------------------------------------------------------------

And secondly, maybe there's a Qt way to detect the systems platform? Something like this pseudo-code:

if (QApplication.platform() == "mac"):
    makeMacApplicationMenu(macMenuBar)
    makeOtherMenuItems(myMenuBar)
else:
    makeMyApplicationMenu(myMenuBar)
    makeOtherMenuItems(myMenuBar)

if (QApplication.platform() == "mac"):
    makeMacApplicationMenu(macMenuBar)
    makeOtherMenuItems(myMenuBar)
else:
    makeMyApplicationMenu(myMenuBar)
    makeOtherMenuItems(myMenuBar)

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Is there a way with Qt3 (or maybe Qt4) to implement this platform-uniform menu?

Thanks a lot for any advice,
Juergen