Battering my head against FAM, again. Seems it on -some- setups is a bastard that locks /mnt/cdrom, while on others it works. yesh.
To be even more annoying, 2.7.0 doesn't have a DNotify patch, (which does lock) and therefore can't lock the cdrom. if It has DNotify it still doesn't always lock. I just don't know what the case is here :/
I guess it'd be simple to just use it with xinetd and be done, but that feels like cheating.