Data Protection in Apple iOS before 7 allows attackers to bypass intended limits on incorrect passcode entry, and consequently avoid a configured Erase Data setting, by leveraging the presence of an app in the third-party sandbox.
http://www.securitytracker.com/id/1029054
http://support.apple.com/kb/HT5934
http://lists.apple.com/archives/security-announce/2013/Sep/msg00006.html