Q: AVCHD footage won't let me use transitions

Hi,

I just imported some AVCHD footage into Final Cut Pro 7 using Log and Transfer.

When I try to add a transition between two clip it keeps saying there is not enough footage to do the transition. The thing is, there is enough footage as the clips I'm using are both about 2min long.

Any ideas on what could be the problem?

Thanks a lot.