Some background: I know this is a topic of much discussion, but I searched and couldn't find an exact answer to my question. I have an iPhone 3g (which I pay for a data fee on) that I love. My Dad would really like an iPhone as well, but can't afford the $30. The question: I have an extra 3g that I got from a friend, could I jailbreak and unlock it to work with my Dad's SIM card? I was thinking I would put my SIM card into the extra iPhone, Jailbreak it, unlock it and use his SIM. Can it be done? I dont see why it can't, but I haven't found evidence to support this.