I have an iphone 3GS running IOS version 4.0 with baseband 5.11.07. I haven't jailbroken since the release of 4.0 last year using Pwnage tool. What do I need to do in order to upgrade? Is there a software upgrade (4.1 or 4.2) that allows me to keep my current phone unlocked? I read the dev team blog, but I've been out of the loop so long that I'm confused. Thanks in advance!