I have created software (CryproList) that can be used to encrypt PINS, Emails, Passwords and any other code. It is tested on Sony Ericsson phones W200/W300 and ELM phones. Probably it can run also in other SonyE phones that have Java MIDP 2.0 or higher installed in them.
The codes can be loaded/backup on a PC and can be decrypted by the DesktopCryptoList which is a PC version of CryptoList.