Palm has posted a security update for the Treo 650, 680, and Treo 700p. This update patches a loophole, where someone could gain access to a Treo that has been locked. Essentially, someone can unlock a Garnet-based Treo by tapping the Emergency Call option (available when the phone is locked) and then using the Find feature in the phone app to gain access to the rest of the system.
This update disables the use of the Find command while in Emergency Call mode, fixing the security bug. Palm encourages all Treo 650, 680, and 700p owners to update their devices.
Treo 650 Security Update
Treo 680 Security Update
Treo 700p Security Update