With the release of iTunes 9.1, many new features included a complete Books section were introduced but several users who were using Jailbroken iPhone OS 3.1.2 were facing syncing problems. Those who have used blackra1n to jailbreak their iPhone 2G/3G/3Gs or iPod touch on firmware 3.1.2 and have upgraded to iTunes 9.1 can now use BlackBreeze fix for blackra1n from ih8sn0w.

Important

Now you can do untethered Jailbreak of your iPhone 3G/3Gs running latest firmware 3.1.3 with "Spirit".

Step by Step iPhone 2G/3G/3Gs Firmware 3.1.3 Jailbreak Guide Using Spirit

Procedure:

1) I assume you already have iTunes 9.1 (Windows). If not, download it from here.

2) Download BlackBreeze from ih8sn0w.

3) Once downloaded, run it. It will show the following dialog box:
blackbreeze-for-iphone

4) Click “Fix my ra1n” and it will ask you to locate blackra1n.exe file on your computer. Specify it. And then after processing, it will display this dialog box if it was successful in fixing blackra1n.exe:
blackra1n-fix

Now you will notice that it has create another file named “blackra1n-fix.exe”. So you will have to use this Jailbreak tool next time you jailbreak your iPhone or iPod touch firmware 3.1.2

Here are extensive tutorials to Jailbreak and unlock your iPhone or iPod touch

Unlock and Jailbreak iPhone 2G, 3G and 3Gs:

Jailbreak iPod touch:

[via ih8sn0w]