Hey there. I just wanted to know if it was possible to use a non-iPhone data plan with an iPhone 4. I know it was possible with a 3GS running iOS 3.x by changing the APN settings I believe. Can anyone confirm this still works on the iPhone 4? I mean I have have the sim card of a compatible phone that has a plan like "Data Unlimited" for $15/month : http://www.wireless.att.com/cell-phone-service/services/serviceDetails.jsp?LOSGId=7295504394&skuId=sku1160057&catId= or "Messaging & Data Unlimited" for $30/month : http://www.wireless.att.com/cell-phone-service/services/serviceDetails.jsp?LOSGId=7295504394&skuId=sku1160058&catId= or "Messaging 200 & Data Unlimited": http://www.wireless.att.com/cell-phone-service/services/serviceDetails.jsp?LOSGId=7295504394&skuId=sku4510225&catId= could I just cut the sim and put it in my iPhone 4 (or change the sim online to my new iPhone 4 microsim) and just change the APN settings so I wont get the "Could not activate cellular data network: you are not subscribed to a cellular data service" error? Also, is this "Data Unlimited" package really unlimited or does it have a 5GB cap or something? Also can ATT or does ATT usually do anything about iPhones on a non-iPhone plan? I used to have a crappy samsung phone on a family plan with just voice ($9.99 for the extra line) and I simply put that sim on my iPhone 3GS and used it just fine for about 9 months or so... Thanks. Edit: Ps: If anyone wants to pm me the info or their story instead of posting it publicly, please feel free to do so.