An option to note on the Treo is the ability to lock your wireless mode either upon power off or immediately as well as locking the total communicator (wireless as well as PDA) immediately. You can also designate up to three emergency numbers which can be dialled even if the unit is locked.

This functionality can be accessed through the Phone Book, Options, Security Preferences.

A few things to note: If you choose the total lock of the communicator functionality, once you unlock it and want to relock it again, you have to go back into Options, Security Preferences and re-select the option. I guess this feature is intended if you leave the unit at your desk and wander off for a bit.

Additionally, the intital password to set these options should be the last four digits of your phone number.