What would really help is if you enabled debug logging, and then sent yourself a few MMS from a extant contact. After about five or ten minutes, send logs through the app. Please make sure to mention the number that these MMS are supposed to come from and "from droidforums or something so I know its you.
With some good logs thus should be easy to fix - would have done it already but we don't have CDMA in Europe!
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