To get your data and mms working on iphone update 3.1.3.
Requires SinfuliPhone Repo
Click "sinful iPhone"
Click "MMS & Tethering Settings"
Click "install" then "confirm"
Then open Settings>General>Network>Cellular Data Network
The APN should be wap.cingular. If it's blank or something else like "phone", change it to "
Click on your home button to exit out of settings and your data and MMS should be working in a few seconds.