iH8sn0w has released the BlackBreeze utility Fix for Blackra1n that resolves the incompatibility and syncing issues with the new iTunes 9.1 for windows users. Mac users must not have any problem while upgrading to iTunes 9.1.
Using BlackBreeze is extremely simple. To troubleshoot blackra1n RC3, just start BlackBreeze and then select blackra1n RC3. Select the directory where you want to save the fixed blackra1n RC3 executable file (blackra1n-fixed.exe). Use the patched and updated blackra1n RC3 jailbreak utility to fix iTunes 9.1 issues that will allow you to sync your iPhone 3.1.2 with iTunes 9.1 easily.
Download BlackBreeze to Fix blackra1n RC3 with iTunes 9.1
blackbreeze for windows