Ultrasn0w is an iPhone 3G unlock tool developed by iPhone Dev Team that supports the new iPhone OS 3.0 firmware. Ultrasn0w will unlock any iPhone 3G and insert the SIM of your choice irrespective of any GSM cellphone carrier. Make sure that you have upgraded to iPhone OS 3.0 (04.26.08 baseband). Ultrasn0w ill work only if your iPhone is jail-broken. You can jailbreak your iPhone 3G using redsn0w or PwnageTool.
Step by Step Process to Unlock iPhone 3G using UltraSn0w
Step -01- Launch ‘Cydia Installer’ from your SpringBoard and click Manage tab at the bottom of your iPhone screen.
Step -02- Navigate to Sources -> Edit and then click Add (at the top left of the screen)
Step -03- Enter URL http://repo666.ultrasn0w.com/ and press the Add Source button.
Step -04- Click Search and search for ultrasn0w and select ultrasn0w from the list of packages.
Step -05- Now, Simply click the install button at the top right of the screen to install Ultrasn0w.
Step -06- Once the Ultrasn0w installation is completed successfully reboot (Power Off and then Power On your iPhone)
Important Note – T-Mobile users must disable 3G before installing and using ultrasn0w to unlock iPhone 3G.
Also see ultrasn0w video demo to unlock iPhone 3G running iPhone OS 3.0 firmware.