iMovie '11 on Mountain Lion does not see Canon Vixia HG20, Lion does

I have 2 Canon Vixia HG20s and an HG21 that I had previously used with iMovie. When I plug the cameras into any of my Mountain Lion systems, iMovie does not see the camera to import from. On my MacBook it only sees the EyeSight camera.

I know I had imported from these cameras when I was still running Lion. In fact, I still have one Mini running Lion Server. I installed iMovie onto it and plugged in one the HG20s. It immediately recognized it and offered to import the videos. I unplugged it and immediately moved it to the MacBook with Mountain Lion, and it's not recognized.

The one thing I'm not sure I have tried is on another Mini that was upgraded from Lion to Mountain Lion. I will be trying that tonight.

What can be done to allow me to import my videos, something I USED TO be able to do?

Thanks!