Its simple.
1.) get an old AT&T phone (one that is MMS capable) and a new SIM card. (You can get an old phone and SIM cards from ebay if you don't have one. The Blackberry actually works best b/c you can get a plan that has unlimited email, unlimited internet, unlimited text, etc. for $50 a month)
2.) call AT&T and tell them you need to switch phones on your plan. AND tell them you also have a new SIM card. You should probably tell them you lost your iphone b/c they may ask where your old SIM card is. They're a nosy bunch of folks!
3.) You may also need to have them set up your voicemail again.
4.) After changing your plan to the new phone, wait a day or so, and then put the SIM card of the new 'old' phone into the iphone.
5.) You now have swirly mms.
You cannot call AT&T and get the WAP push enabled! They will not do it. This is the only way around it...not to mention is easier and faster.
Different settings in swirly work. You may just have to play around with it.
MMSC: mmsc.cingular.com
Proxy: wireless.cingular.com
APN: wap.cingular
u may have to switch up the phone options from time to time. at least I do.
Good luck!