MMS is coming soon but the network operators aren't always easy to deal with. Right now, we put a link in the sms, that way you can send any file type.
Getting an MMSC exposed from a network operator is a nigh-impossible task (source: I'm a telecom junkie).
The MMSC infrastructure is unnecessarily complex and, for some ungodly reason, is seen as a proprietary network advantage. Your best bet is to make an end-run around the carriers by partnering with an aggregator like Acision (or someone smaller if you lack the volume).
MMS is one of the most difficult things to get carriers to expose :/...
