SMS status?

Hi all, I work in a research lab and we're interested in using your stack to send SMS. I've got some time on my hands and a working OpenBTS stack (USRP), so I will probably go ahead and start implementing it in the mobile app. Before I start I just wanted to ask first about the status of mobile-originated SMS? I saw some traffic in the archives a few months back from Gianni about mobile-terminated SMS, but nothing recent about mobile-originated SMS. Barring that, any suggestions on where to start? :) I'm kinda new here. Assuming I get something solid working, I'd of course be willing to contribute it back to the codebase. Thanks, Andrew