Hey, im unlocking a iphone 3gs for the first time. its on 05.15.04 and 4.2.1. I understand i need cfw to jailbreak it and unlock it. but how do i get this? i unlocked my 3g before but someone sent me a cfw for it so i didnt have to do much because the program i used before wasnt creating cfw for me. Btw im on windows.