Sorry, should have mentioned a bit about that. The Password Safe format is public, open, and available here [1]. There's also plenty of code/libraries you can use to write your own clients, e.g. Javascript [2], Java [3], Python [4]. For what it's worth the core data encryption is done using the Twofish cipher. Hope that helps.
[1]: http://sourceforge.net/p/passwordsafe/git-code/ci/master/tre...
[2]: https://github.com/scintill/pwsafejs
[3]: http://sourceforge.net/projects/jpwsafe/
[4]: https://github.com/ronys/pypwsafe