Opaque I think the basic problem you have is the same as mine. Mandrake use supermount, Redhat don't.
Supermount is excellent it allows you to just insert and eject CD's and they get mounted/umounted automajically.
You could go to the supermount home page and patch the RH kernel, or you could add 'user' as one of the options for the cdrom entry in /etc/fstab. That should allow users to mount/umount the CD's.
I am running RH 7.1 and am going to try and patch my kernel, I'll let you know how it goes.