iPod will not eject, iMac hangs

I have a intel based Mac using Lion. After charging/syncing my iPod or my wifes iPod, and attempting to unmount / eject the iPods, the iPod's display a conneced status. Disconnecting the iPods result in a hung OSX, forcing a power off to reboot. All software is up-to-date on all devices.

Thanks, Eric 7210