Unlock iPhone OS 4 Beta on iPhone 3G with ultrasn0w

Now that we have a jailbreak (developers only) for iPhone OS 4 Beta, and an upgraded version of Fuzzyband (Baseband downgrader). Technically, iPhone 3G can now be unlocked on the latest iPhone OS 4 Beta, provided that you have one of those rare iPhone 3G’s with 05.08 bootloader that is downgradable to 05.13.03 baseband of OS 4 to 04.26.08 so that ultrasn0w can unlock it.

Unlock iPhone 4.0

NOTE: I haven’t tested this on my iPhone 3G. This is only for iPhone 3G with 05.08 bootloader. Proceed only at your own risk.

Step 1: First follow the complete step by step guide posted here to jailbreak iPhone 3G on iPhone OS 4 Beta firmware.

Step 2: Using Fuzzyband, downgrade your baseband 05.13.03 to 04.26.08. Step by step instructions for downgrading baseband can be found here.

Step 3: Now start “Cydia” on your iPhone and touch on “Manage” tab on the bottom. Now touch on “Sources” as seen in the screenshot below:

Note: T-Mobile users should disable 3G before installing ultrasn0w.

Unlock iPhone 4.0

Step 4: Touch on “Edit” and then on “Add”. You will be prompted to enter a url source as seen in the screenshot below. Type “http://repo666.ultrasn0w.com and touch on “Add Source”.

Unlock iPhone 4.0

Cydia will now automatically update your sources by following a series of automated steps.

Step 5: Once the repository has been added successfully, Search for “ultrasn0w” in Cydia and install this application.

Unlock iPhone 4.0

Step 6: Now simply restart your iPhone.

If all goes well, you should now have an unlocked iPhone 3G running on iPhone OS 4 Beta. Let us know if this worked for you in the comments section below.

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