As we expected, the unofficial build of PwnageTool has been released for jailbreaking iOS 4.0.2, the latest iOS firmware from Apple released last week in order to patch the PDF exploit. This unofficial build can jailbreak iPhone 3GS (old bootrom only) using iOS 4.0.2 custom firmware.
If you have iPhone 3GS with iOS 4.0.1 (jailbroken with JailbreakMe star) and the PDF patch, you don’t even need to update to iOS 4.0.2. This guide is only for those who have accidentally upgraded their iPhone 3GS to iOS 4.0.2
Guide to Jailbreak iPhone 3GS on iOS 4.0.2 using PwnageTool
I repeat, this unofficial PwnageTool build works only on iPhone 3GS with old bootrom.
1. Download and install the latest version of iTunes.
2. Start iTunes and backup your data.
3. Download Unofficial build of PwnageTool (http://www.megaupload.com/?d=63NSJXYL) and the original iOS 4.0.2 for iPhone 3GS. Move all these files to your desktop.
4. Start PwnageTool and select your device.
5. PwnageTool will now automatically detect the correct firmware for your device. Click on “No” when PwnageTool asks you “Do you have an iPhone contract that would activate normally through iTunes?”. Clicking on “Yes” will update your baseband to the latest version. Click on “Yes” only if you are on an officially supported carrier like AT&T.
6. PwnageTool will now create the custom .ipsw file for your iPhone which will be jailbroken.
7. Once the custom .ipsw file is created, you will see a confirmation message “ihaz Success”
8. Now restore your iPhone to this custom firmware 4.0.2 that you just cooked using PwnageTool for your iPhone. Click on your phone icon from the sidebar in iTunes. Now press and hold left “alt” button on the Mac keyboard and then click on “Restore” (Not “Update” or “Check for Update”) button in the iTunes and then release the “alt” button. Select the required custom .ipsw file and click on “Open”.
9. PwnageTool will now do the rest for you. Do not do anything silly during this time, just wait for the tool to complete the jailbreaking process.
10. Unlock your newly jailbroken iPhone 3GS on iOS 4.0.2 using UltraSn0w 1.1-1
Restore the backed up data in iTunes back to your phone. If you are an iPhone 3G user use this guide to jailbreak iPhone 3G on iOS 4.0.2 using RedSn0w.
Disclaimer: This is for information and education purposes only. Moreover, this being an unofficial release, I do not recommend using it as it might have some bugs