Perhaps a different method should be used in that case.  It would be good to have the ability to sandbox attachments.  How about each registered user gets a attachment folder created when they first go to upload.  All subsequent attachments from that user go into the sandboxed user folder.

I notice that even with attachments off users can click on the hyperlink icon in FCK and get a dialog to link a file on the site. They can then browse through all directories in the portal.  This is nuts!  How can I lock this down and still allow people to insert hyperlinks?