Ok, so I just bought an iPhone 3gs on eBay because I don't have at&t and I just wanted a super iPod. Well the iPhone I bought has no SIM card, so when I turn it on, it says "No SIM card inserted. Insert a valid SIM with no PIN lock to activate iPhone." What do I do here? I have Sprint so I have no SIM card. Just wanted to use this as a super iPod as stated before. Do I need to jailbrake it to work or what?