Reinhold, just to clarify, I wasn't told that you couldn't have quotas on multiple filesystems, just that SME didn't support it. Meaning, the server-manager panel would only check the quotas on the root filesystem, not filesystems mounted after OS installation. It's listed in the bugtracker at:
http://no.longer.valid/mantis/bug_view_page.php?bug_id=0000125While this does not mean that you can't have the quota working on additional filesystems, it just meant that, for newbies like me, it wasn't easy to set up. I scoured the forums for help on this issue before posting to the bug tracker and found none.
For a refresher of my previous posts on this topic, hit:
http://forums.contribs.org/index.php?topic=24391.msg99399#msg99399Oddly enough, it was you and I which filled that thread

I ended up enforcing quotas the old fashioned way - emailing users to warn them of excessive file accumulation.