VCD filesystem?

Hey all...I wasn't sure which forum to post this in, so I opted for general.

Anyone know what filesystem VCDs use? I only ask because OS X seems to be incapable of mounting VCDs. I insert one and get the error message:

"You have inserted a disk containing volumes that MacOS X can't read. To use the unreadable volumes, click Initialize. To use only the rest of the disk, click Continue"

and then it gives the options "Initialize", "Cancel", and "Continue".
Clicking cancel ejects the VCD. Clicking on initialize brings up Disk Utility, but does not show the VCD. Clicking on continue does nothing, but makes it impossible to eject the VCD w/out rebooting.

Interesting to note: OS 9.1 can mount VCDs w/out much of a problem, however, if you go into Apple System Profiler, it will not show anything mounted in your optical drive (it says no volumes mounted, even though I could see it on my desktop and was watching the video on it in QuickTime).

So, what is the filesystem on a VCD? and when (if ever) can we expect it to be supported? Any ideas?

thanks for your help.