Mapping keyboard shortcuts using the Command (Apple) key.

Hi,

I want to be able to zoom in and out of the timeline by pressing the Commnd Key (or Apple Key) plus the + or - key on my numeric keypad on the right side of keyboard (not the numbers on top of my keyboard). 

Is there a way I can do this in Media Composer 6?

I did it in FCP 7 without a problem.

Thanks

Mac Pro

Media Composer 6