I've recently changed over to 2degrees, kept my phone (Sony Ericsson Xperia Active) which worked fine on Vodafone.
Cannot send or receive MMS messages
My husband has also changed over, he has a Motorola Defy, and it appears he cannot send or receive them either (although it's hard to tell who is and isn't able to send when we're testing between our phones!).
The message says 'sending' before resigning and just saying 'queued'.
I've installed, removed and installed again the settings sent to me off the 2degrees site.
I've turned my phone off and on again...somewhat frustrating.
Any help would be appreciated