iOS 4 jailbreak software when released, was compatible only with iPhone 3G and iPod touch 2G (non-MC models) and iPhone 3GS (old bootrom). For 3GS phones to be jailbroken it required to have been jailbroken or pwned with any software such as blackra1n except Spirit apart from its requirement of having old bootrom.

The users would have experienced that if their iPhone 3GS was not jailbroken with any software except Spirit, iTunes would have thrown an error when they attempt to restore their phone with custom firmware.

SnOwbreeze 1.6.2 was then developed for Spirited devices. Now, users can also use Spirit2Pwn patch for restoring the iPhone 3GS on iOS 4 custom firmware. For this, the phone has to be previously jailbroken using Spirit.

The steps to jailbreak using Spirit2Pwn are as follows :

1. Start Cydia on the iPhone 3GS with old bootrom and ensure that it has already jailbroken using Spirit.

2. Go to ‘Manage’ tab and click on ‘Sources’.

3. Touch ‘Edit’ followed by ‘Add’ tab.

4. Enter the url : http://repo.woowiz.net and click ‘Add Source’.

5. Cydia will automatically get updated. Just search for ‘Spirit2Pwn’ in Cydia and say install.

6. Similar step has to be followed to jailbreak iOS 4 on iPhone 3GS using PwnageTool 4.0/4.0.1 on Mac and SnOwBreeze 1.6 on Windows.