This project is now archived as I haven't had interest nor time to work on this.
xfslove has made a fork that is somewhat more up to date, check it out at https://github.com/xfslove/smsj
Was created as a way for me to learn more about SMS and MMS (was supposed to be the big next thing).
Orignally published at sourceforge: http:https://smsj.sourceforge.net/
The first smsj checkin was done at Mar 15, 2002