Flash cs3 and Keyboard Shortcuts

Hi Guys

I trying to learn cs3 flash but have encounted some problems with my keyboard and assigning shortcuts

I trying to assign a shortcut for insert blank keyframe (f7) but when I go to assign my own shortcut it will not recognise me pressing any of the f keys after f6, I know these are assigned for Itunes for skipping tracks and what not but is there any way to tell the mac that when flash is open and running I want f7-f12 to do other things?

Sorry its pretty hard to explain, hope you guys understand

Matt