i have update my iphone to 1.2 version and i have upload the" SimFee" and "AnySim" software to my iphone. but whenever i strat those programs, the screen will be blank for a while, than return back to main screen. i activited my iphone with itunes7.4 and currently using ATT. however, i want to use my T-mobile sim card into my iphone. Can anyone help me solve this problem??