Does anyone have any suggestions for unlocking a Verizon iPhone 4s for use on T-Mobile? I have called Verizon a couple of times, but they only want to unlock it for international use. I want to use it domestically. I get an error when I insert the T-Mobile SIM card that it is not valid with my phone's activation policy, so I can tell it hasn't been unlocked by Verizon. Does anyone have experience with unlocking services for something like this? Thanks!