The DevTeam has just released PwnageTool 4.0 to Jailbreak iOS 4 on iPhone 3G, iPhone 3G and iPod Touch. PwnageTool 4.0 jailbreak tool creates custom ipsw firmware files for iOS 4.0 for iPhone 3GS, iPhone 3G and iPod touch 2G (non-MC model only) that updates your iPhone OS to iOS 4 without updating its baseband. Follow the step by step guide to jailbreak your iDevice using PwnageTool 4.0 easily.

The tutorial can be used to jailbreak following iDevices
- iPhone 3G but only with old iBoot
- iPhone 3G
- iPod Touch 2G but not MC
Requirements:
- PwnageTool 4.0 [Download Link]
- iOS 4 original firmware of your device saved on your computer (Download Here)
- If you have an iPhone 3G or 2G iPod Touch you have to start with a device that mounts on firmware 3.1.2 or 3.1.3, which has already been Jailbroken and unlocked with PwnageTool or RedSn0w, but NOT with Spirit. If you have an iPhone 3G you need from firmware 3.1 or 3.1.2. If you are not in this situation, you first downgrade and then proceed.
- iTunes 9.2 installed on your Mac;
How to Jailbreak iOS 4 using PwnageTool 4.0
Step 1: Download and install iTunes 9.2.
Step 2: Launch iTunes 9.2 and sync your iPhone with your PC for backup.
Step 3: Download PwnageTool 4.0 and the original iOS 4.0 for your version of iPhone or iPod touch. Copy all the files to your desktop.
Step 4: Start PwnageTool 4.0 and select your device:
Step 5: PwnageTool 4.0 will now automatically detect the correct firmware for your device.
Step 6: Click on “No” when PwnageTool prompts “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.
Step 7: PwnageTool will now create the custom .ipsw file for your iPhone once you notice the screen which says “ihaz Success”, ensuring that the requested .ipsw file has been created successfully.
Step 8: Now its time to restore your iPhone to this custom firmware 4.0 for your iPhone or iPod touch.
- Click on your phone icon from the sidebar in iTunes.
- Press and hold left “alt” button (“Shift” button on Windows) on the keyboard and then click on “Restore” (Not “Update” or “Check for Update”) button in the iTunes
- Now, release the “Shift” button.
iTunes will now prompt you to select the location for your custom firmware 4.0. Select that custom .ipsw file and click on “Open”.
Step 9: Wait for a while till iTunes installs the new firmware 4.0 on your iPhone. After the installation is done, iPhone will restart automatically.
Voila! You have successfully jailbroken iPhone on iOS 4.
If you want to unlock iPhone on iOS 4.0 (Any Baseband), then follow the complete step by step guide posted here to unlock iPhone 3GS and iPhone 3G, on iOS 4, on any baseband using Ultrasn0w 0.93.
Step 10: After jailbreaking and unlocking iOS 4, you can now restore all your settings, apps, contacts and photos to the newly installed firmware version iOS 4 by restoring the backup that you made in Step 2 from iTunes.
