Somewhere in this link:
http://www.knoppix.net/forum/viewtopic.php?t=12510

I got my dvd drive to work. Had to create symlinks that point to the drive.

Post this info

ls -la /dev/sda*
ls -la /dev/dvd

May need to create the symlinks.

dmesg in console and near the top should be info about the drive. The scsi# is needed because it is associated with the corresponding scd#.

Check the last page of that thread. Got it to finally work.