I have an Iphone 3Gs, old bootrom, baseband 05.07.11, currently jailbroken and unlocked on firmware 3.1. I want the new features of ios 4.0, but still want to be jailbroken and need to be unlocked. I hear that it is very possible to jailbreak and unlock my device on 4.0, but i need a solid step by step description on what to do and what programs/tools to use, to not make my device unuseable. It would be extremley appriciated. Its either that, or i sell this phone and buy one that it already jailbroken on 4.0. Its extremley important. Thanks alot to anyone who helps.