i have currently unlocked and jb'd newer version of 3gs. it is on 3.1.2 7D11 carrier 5.0 05.11.07 modem firmware. i want to have it up to 4.1 or 4.0 or 4.2 or whatever it is better than 3.1.2. well let me restate it. i want it to be on firmware higher than 4.0. like 5 months ago, it was not able. but i heard it could not enabled. any ideas how to do it???