Is it an empeg feature that his kernel boot log indicates that the second drive is /dev/hdb, while everyone in the thread is talking about /dev/hdc. I don't have two drives to verify, but to me this looks like it could be caused by a mk1 image that was installed on a mk2 player.

In any case, ps (or better lsof) could be used to see whether any unusual processes are running that have open filehandles on /drive1.