Ok, so I am trying to jailbreak, unlock and use my iphone 3g on the tmobile network. My husband tried to help me and he upgraded the firmware to 4.1 which (apparently) is unbreakable. So, my question is is there a way to revert the firmware to 3.0? I have spend the better part of 3 days doing this and right now I am just wishing I would have purchased an unlocked phone. I have a mac and a pc so either format is ok, although my iphone seems to be responding more favorably to the mac.