SwirlySpace, developers of the jailbreak app SwirlyMMS have released a video demonstrating how you can send and receive MMS on the iPad using a modified version of SwirlyMMS for iPhone.
The MMS is sent natively via carrier networks and not via SwirlyNet.
They are working on a GUI for the iPad, to complete the port, but all technical pieces seem to be in place.
Swirly was the first to bring the MMS feature to the jailbroken iPhone before the feature was available in iPhone OS 3.0.
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