[Mac] [1.1] Preferences disabled after accessing 'About MuseScore'

After various activity, the menu option MuseScore->Preferences... becomes greyed out and the only way to restore it is to exit and restart.

To reproduce:
1) Start MuseScore
2) Verify Preferences... is available.
3) Go to MuseScore->About MuseScore
4) Click OK
5) MuseScore->Preferences... is now disabled.

Installation information:
MuseScore Version 1.1, Revision 4611
Qt Version 4.7.3
Mac OS X 10.6.8
MacBook Pro, Intel Core i7 quad-core processor, 4GB memory
Language: System (English)

Hopefully this is enough information. Let me know if there's anything else you need. Great program otherwise.

Thanks,
~~Anya