Greetings~ I have an original iphone version 3.0.1. I have a Mac with I believe Tiger (Mac OS 10.4.11) My 2 year AT&T contract finally just expired. So my iphone now reads "No Sim" where the AT&T bars used to be. The AT&T service works terribly in my apartment so I've been anxious to try T-mobile. Can someone clarify some things for me? -Can I switch to t-mobile and keep my phone number? -Can I switch to t-mobile without renewing my at&t contract? -How do I unlock my phone so I can do this? Every tutorial I seem to come across is either for the 3G or the old iphone but only up to version 2.0.1 or only if you have leopard or its from 2 years ago and at least one of the downloads or apps no longer exists. I'd really appreciate any help or guidance on this! Thanks.