I'm using an HTC Magic on T-Mobile UK and have so far been unable to get MMS working. I've put in all the settings as has been described for the G1, which I assume are the same but so far have had no luck getting them to work. I also have a problem where once I configure the APN it disappears from the list when I put port numbers at the end of the MMS settings.
If anyone can help and point me in the right direction that would be great. I've searched and searched and had no luck so far.