Here comes another update of Sn0w Jailbreak. The developer has released an updated version of Sn0w breeze jailbreak tool for iOS 4.2.1. The new version os Sn0wbreeze R3. The tool is released specifically to address the issue of iBook restriction for jailbroken iOS devices.
Rest of the features in the Sn0wbreeze 4.2.1 are same like the previous version. tool allows you to create custom firmware for an untethered iOS 4.2.1 jailbreak on Windows OS. The tool uses the same exploit found in the Greenpois0n RC5 jailbreak tool by the Chronic Dev Team.
For those who are unaware of Sn0wbreeze jailbreak tool, it helps you build a custom .IPSW file on Windows operating system very similar to the process of creating .IPSW using PwnageTool for Mac.
For those who are unaware of the iBooks restriction, the version 1.2.1 of the iBooks denies to open books on the phones that are jailbroken. It is because Apple has implemented some anti jailbreaking tricks in it. iBooks is implemented with a process which involves the running of unsigned code attempts. These type of attempts are only executed by the jailbroken phones. So it will detect that you are using a jailbroken iPhone and will prompt you a message to restore your iPhone device.
Download Sn0w Breeze 2.2 R3 For Windows
Follow the STEP BY STEP GUIDE to use Sn0wbreeze 2.2 on Windows
Update: New version has been introduced: Sn0wbreeze 2.2.1