IBM DB2 UDB 8.2 before Fixpak 7 (aka fixpack 14), and DB2 9 before Fix Pack 2, on UNIX allows the "fenced" user to access certain unauthorized directories.
http://www.securitytracker.com/id?1017731
http://www.securityfocus.com/bid/22729
http://www-1.ibm.com/support/docview.wss?uid=swg1IY87492