One of the biggest buzz of this year is about to come true. Come June 2014 and you did be able to see yet another Internet giant joining the arenaread more...
How to: Unlock iOS 4 on iPhone 3GS Using Blacksn0w [Video]
msft.guy succeeded to unlock iOS 4 on iPhone 3GS by Blacksn0w, also I should refer that you have to preserve your baseband to 05.11.07 using PwnageTool. msft.guy formaly describe the new batch file blacksn0w4GM.tgz as follow:
Patched for 3GS GM; manual load; run /bin/blacksnow.sh after booting. Blacksn0w unlock (C) geohot http://blackra1n.com
Important Note:This unlock job work on 3GS with 05.11.07, also you have to reapply the patch every time you reboot your device. If you are not advanced to doing this unlock you have to wait the official unlock tool after two weeks.
Step 1: Follow the iPhone 3GS Jailbreak using PwnageTool bundles instruction here.
Step 2: Download latest version of Balcksn0w patch for iOS 4.0 GM here.
Step 3: Follow the instruction on the next video to unlock the iPhone 3GS on iOS 4.0. (video was originally meant for Beta 4, but it applies to this GM release too.
Update 1: Now Blacksn0w RC2 has been Released to Unlock iOS 4 on iPhone 3GS using Automatic Method, More Details from Here.