I am currently using a regular dumb phone. I read a news article about how you could cut up a regular sim card and use it in the iPhone 4. If I buy an iPhone 4 on ebay to avoid the data plan, can I still use this cut up sim card in the iPhone 4 and avoid the data plan? Also, I read that At&t automatically detects that I am using an iPhone 4 without a data plan and forces me to get a data plan. Is this true? The reason why I don't want the data plan is because I am on a college campus that is fully covered by Wifi. Thanks in advance for any help.