We have a (public-use) Mac (running 10.6), which also has Linux installed on a separate partition. After every reboot, the first person who logs in gets a message "The disk you inserted was not readable by this computer," and is asked to initialize, ignore, or repair. We don't have ext3 drivers installed on the Mac side, and we don't want them installed. But we also definitely don't want someone to hit "initialize" and wipe the Linux partition.
Is there a way to tell the OS to never even try mounting it?