Your favorite Apple, iPhone, iPad, iOS, Jailbreak, and Cydia site.
06-26-2010, 02:50 AM #1How to Unlock iPhone 3GS/3G on 4.0 Firmware
All current iPhone 3GS/3G basebands can be unlocked on firmware 4.0 using the dev team's ultrasn0w 0.93. That means if your jailbroken your iPhone 3GS old bootrom (mac jailbreak guide | win jailbreak guide) or jailbroken iPhone 3G (mac/win jailbreak guide) to 4.0 you can unlock it!
Turn on wifi and connect to your network.
Go to Cydia.