How to: Jailbreak iOS 4.0 with PwnageTool

After we announced the iOS 4.0 jailbreak by RedSn0w 0.9.5 on iPhone 3G, and however you need to be official carrier since on updating to iOS 4.0, your baseband will be also automatically updated to 05.12.04 for which no official unlock tool is available till now, so you should preserve your baseband by unofficial PwnageTool v4.0, this is the new from the developers, this can be done using the updated PwnageTool bundles from msft.guy for iOS 4.0 GM build.


Important Note:
I have to refer that we are using now unofficially build of PwnageTool,so performing the following instructions will be at your own risk, otherwise you have to wait the official tool which will be released soon.

Supported and Unsupported Device(s):
iPhone 3GS Only, which hase been jailbroken with redsnOw, PwnageTool, Blackra1n or SnOwbreeze. If you have newer bootrom, and has only jailbroken with Spirit so this will not work, you will get 1600/1604 error when restoring the custom cooked firmware wia iTunes.

Required Software:

• Jailbreak Bundle for iPhone 3GS 4.0
• Pwnagetool 3.1.5 for Mac
• Redsn0w 0.9.5 Beta 4 ((needed to extract cydia app and replace with one present in Pwnagetool 3.1.5))
• iTunes 9.2 (only available for Mac)

Step by Step How to Jailbreak iOS 4.0 on iPhone 3GS Using PwnageTool:

Step 1: Download iPhone 3GS 4.0 Bundle and all the tools and place it on Desktop.
Step 2: Right click Pwnagetool.app (Pwnagetool 3.1.5 for Mac OS X) and click on ‘Show Package Contents’.

Step 3: Browse to Contents > Resources > Firmware Bundles
Step 4: Now copy the custom bundle iPhone2,1_4.0_8A293_bundle.bundle from iPhone2,1_4.0_8A2943_bundle.zip to FirmwareBundles of Pwnagetool.app

Step 5: Right click on redsn0w.app and ‘Show Package Contents’ and browse to Contents > MacOS. Copy Cydia.tar.gz on your desktop and extract its content.

Step 6: Copy Cydia into PwnageTool.app. For this, you need to right click on Pwnagetool.app and ‘Show Package Contents’. Browse to : Contents > Resources > CustomPackages, right click on ‘CydiaInstaller.bundle’ and ‘Show Package Contents’ > Files, and overwrite all the files with the ones you just extracted from redsn0w.

Step 7: Now load PwnageTool.app and create iOS 4.0 custom firmware for iPhone 3GS
Step 8: Once you got the custom .ipsw, you need to restore iOS 4.0 via iTunes. Your iPhone device must be jailbroken. Put the device in recovery mode and restore.
Step 9: Now you are able to run BlacksnOw to unlock iPhone 3Gs iOS 4.0 (Full Guide Here).

Update 1: Ultrasn0w 0.93 has been Released to Unlock iOS 4 on any Baseband, Have fun with the guide posted here.