The unlocking tool Ultrasn0w, which unlocks any network in the iPhone 3G model running on the latest 3.0 firmware of Apple, is released and runs perfectly to unlock the iPhone.

Here are a few details -

• This tool is not available as an app but can be downloaded in a jailbroken phone in which the Cydia app is installed.
• You need to be on the 3.0 firmware and the phone is to be iPhone 3G.

Here is how to install ultrasn0w -

• Run Cydia or Icy
• Please add the repo repo666.ultrasn0w.com to Cydia or Icy. That last “o” is actually the number zero “0”! If you use the letter “o” you’ll get an error.
• Search for ‘ultrasn0w’ in cydia or icy and install ultrasn0w
• Reboot your iPhone 3G

I would be unlocking an iPhone 3G device after a couple of days(after my trip) and then add a tutorial for those who don’t understand how to unlock the phone using Ultrasn0w.
Here is how to Jailbreak iPhone 3.0 firmware and how to unlock iPhone 2G. Also, if you are using the 2.2 firmware and want to upgrade to the latest OS version, then here is a tutorial on how to upgrade to iPhone 3.0 firmware.

Please don’t try to unlock the phone if you have no knowledge or did not unlock an iPhone anytime earlier. Just subscribe and you would see the tutorial very soon.