I've been dealing with this issue for months now, and I have tried EVERY method mentioned, and I can NOT send any MMS, but CAN receive them. Reset's don't work, toggling airplane mode on/off doesn't resolve this. I contacted VZW CS, and they tell me that they were unaware of this issue, despite this thread starting in 2010. If anyone has any clue, please help! This is one of the most frustrating things i've dealt with, because I can't resolve it.
I'm sure VZW won't send me a new phone, because I have this one rooted.