How can my tmobile phone(G1) work in el salvador(central america) ?? or can it work?? help me please.thnk you?

I have been living in El Salvador for over a year and I have a G1 as well. It will work here with your same sim card but you will pay almost $2.00 a minute. It is best to ask T Mobile to unlock your sim card before you leave and then use Tigo here and get a new SIM card with an El Salvador number. Also be careful that you have them turn your internet service off while you are here. The first month I spent over $100 because they were charging me for my internet service and I was not even using it. The SIM cards here cost only about $3.00 and it is prepaid. You can purchase time with as little as $1.00 if you want. Tigo is the best company to be calling the states. They charge $0.09 a minute. While others can charge up to $0.15 a minute. Hope this helps. Have a great trip!!