How to: Jailbreak iPhone 3GS on iOS 4.0.2 with PwnageTool

The unofficial version of jailbreaking tool known as PwnageTool is now released to jailbreak iOS 4.0.2. This tool can jailbreak iPhone 3GS with old bootrom using custom firmware of iOS 4.0.2. It is only for Mac based operating system users (Windows based operating system users can use Sn0wbreeze guide posted here).

This tool creates custom .ipsw firmware file which allows you to update your iPhone to the latest iOS 4.0.2 firmware without updating the baseband. Keep in mind that this PwnageTool Bundles is only compatible with iPhone 3GS with old bootrom.

How to Jailbreak iPhone 3GS on iOS 4.0.2

Follow the step by step guide posted below to jailbreak your iPhone 3GS on iOS 4.0.2 using PwnageTool:

Download and install the latest version of iTunes from here
Start iTunes and sync your iPhone with your computer so that it make a backup of all your important data
Download unofficial release of PwnageTool (http://www.megaupload.com/?d=63NSJXYL) and then move it to your desktop
Download iOS 4.0.2 for iPhone 3GS from here
Run PwnageTool
Select iPhone 3GS and then it will automatically detect the correct iOS 4 firmware file
It will now show you this message: “Do you have an iPhone/iPod Touch contract that would activate normally through iTunes?”, if you rely on a carrier unlock then click on “No“, OR if you are on official carrier like AT&T then click on “Yes“
Now it will create custom .ipsw firmware file for your iPhone, this .ipsw firmware file will be jailbroken
After the .ipsw file is successfully created, it will show you the “ihaz Success!” message
Now restore your iPhone to the custom iOS 4.0.2 .ipsw firmware file you’ve just created using PwnageTool
To restore, start iTunes, “Select” iPhone icon from the left sidebar
Now press and hold the left “alt” key on your keyboard and click on “Restore” button in the iTunes and then release the “alt” key. (Remember don’t click on “Update” or “Check for Update” button)
iTunes will now ask you to select the location of the custom .ipsw firmware file, so select the file that you created in “step 14″ and click on “Open”
Now iTunes will install the new iOS 4 firmware on your iPhone automatically, so let this process complete and be patience during the installation. During this process, the progress bar will show you the installation progress on the screen of your iPhone
Once the installation is successfully completed, your iPhone will reboot automatically, and now you should have a fully jailbroken iPhone on the latest iOS 4.0.2 firmware

How to Unlock iOS 4.0.2 (Any Baseband)

Once you’ve successfully done with jailbreaking your iPhone, then you can unlock it using Ultrasn0w on any baseband. So to unlock your device then follow the complete step by step guide posted here.