iTunes 10.4.1 64 Bit, MacOSX Lion not working

Plain and simple: This Version DOES NOT WORK:

German Error translated:
"The AirPlay device "mycomputername" is not compatible with this version of iTunes."

I can see the squared icon of my computer, but get this message when trying to stream a simple mp3 file.

Please check that your firewall does not block ports 5000 and 7000 (TCP/UDP).

Kr

This error is not at all firewall related, but an incompatibility with iTunes 10.4.1 on MacOSX, obviously. Both firewalls (Mac and Windows) are OFF (even when the Win FW was on, there was an exception for the whole program = all ports) and the error occurs.

And btw: Airfoil from Rogue Amoeba works as a sender with the same setup and another audio player. But Airfoil is only Audio, so I cannot test right now if video from iTunes would work.

Again my setup:
iTunes 10.4.1 on MacOSX Lion, Windows 7 Professional 64 Bit with Aerodrom, both German.

Correction: VIDEO Podcasts and Movies work well from the Mac iTunes, even with sound!

However: a Mp3 file does not play and the attempt gives the mentioned error. Very strange...