Tmobile 3.1 5.11.07 want to go to ios 4

[jeo92109]

Hello Friends,

I own an iPhone 3GS (JB+unlocked) with the 3.1 firmware. I wish to update my device to iOS4 and unlock for Tmobile. I would appreciate if you could give me some directions.

iPhone 3GS

Version: 3.1 (7C144)
Modem Firmware: 5.11.07
Model: MC137LL

Thanks!!!

[qachee]

Same problem here. U can only update to 4.0.2 for which no JB is avaiable. I hope there is a way to selectively update to 4.0.