this is the second time this happened. I do this for friends. I jb and unlock the phone with ultrasn0w. When I put a sim card in, ATT or t-mobile it tells me a different sim has been detected and locks the phone asking for itunes activation. The itunes activation says you have an invalid sim. When the sim is taken out, the phone is activated with no lock screen but obviously will not call since there is no sim in there. can anyone help?