Encryption On PalmOS?

TheTomcat asks: "I'm planning on writing some software for Handspring Visor (or any palmOS device) in PocketC (because I can develop in pocketC directly on the Palm, and I don't have time to learn the SDK), but I would like to encrypt the data that is stored in case the handheld gets lost, stolen, or somehow gets into the wrong hands. Setting the Private Bit is not good enough. Simply, I want simple encryption that is very secure, fast, and can be unlocked by a passphrase (thanks to graffiti). I'm looking at an algorithm called Tiny Encryption Algorithm (TEA), but the spec is dated November 1994, so I'm not sure if it would still be considered secure. Any help would be much appreciated, especially if you can point me at some C source. Thanks!"