Currently have iphone 4 - ATT on 5.0.1 Sometime ago, i JB on iOS 4.x.x . i forget. I've searched and there's so much info I can't wrap my head around it. I need to: - downgrade to 4.x.x - JB and most importantly - Unlock so i can use on Tmobile. Can someone guide me on how to do each of the 3? Thanks!