In response to my previous post of unlocking iPhone 3G, 2G on OS 3.1, I had few people who had broken Rule no.1 (which says that don’t upgrade to OS 3.1 from iTunes) set by Dev Team. For those, here is a solution, downgrade the Baseband.
Update: Jailbreak Unlock iPhone 3G 3GS 05.11.07 using blackra1n with blacksn0w
Pre-requisite: To downgrade your baseband from 05.11.07 to 04.26.08, you must first jailbreak your iPhone 3G running firmware 3.1 by following guide unlocking iPhone 3G, 2G on OS 3.1.
Step 1: Go to “Cydia” and Search for “Fuzzyband” and then install it.
Step 2: Start Fuzzyboard app and click on Downgrade button to start downgrading your Baseband from 05.11.07 to 04.26.08.
Step 4: Now, your iPhone 3G is having an unlockable baseband. Now proceed with Unlocking with Ultrasn0w.
NOTE: Downgrading of baseband will only work on phones that have the 05.08 (5.8) Bootloader. If you do not know your bootloader, run Fuzzyband and it will report the version to you.
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