iPhone 3G fw. 3.1.3 modem ver. 5.12.01 locked to Globe
requirements:
-Unit must be Jailbroken Cydia installed
-Wi-Fi connection
Press to launch Cydia Installer from your SpringBoard.
Press to select the Manage tab at the bottom of the screen.
Press to select the large Sources button
If the ultrasn0w repo is not present press the Edit button at the top right of the screen. Otherwise, skip to next step.
How to add ultra snow repo:
-Press the Add button at the top left of the screen.
-Enter http://repo666.ultrasn0w.com/ as the source url and press the Add Source button.
-Once the source has been added press the large Return to Cydia button.
-Press the Done button at the top right of the screen.
Press to select repo666.ultrasn0w.com from the list of user entered sources.
Press to select ultrasn0w from the list of packages
Press the Install button at the top right of the screen.
Press the Confirm button at the top right of the screen.
After installation completes successfully press the reboot device tab
Once your unit reboots inserted a different carrier sim
Big thanks Iphone Dev team