iBooksFix2 fixes iBooks issue on jailbroken 5.0.1 devices
It's no surprise that Apple has been combating jailbreaking since it's inception. More recently, they have done so by making iBooks crash on jailbroken devices. The jailbreakers have been working hard to combat this but it seems that with every new iOS release, old iBooks fixes become useless.
For those jailbroken on iOS 5.0.1 there is a real easy fix for iBooks. First add the repo http://repo.insanelyi.com to Cydia and then search for iBooksFix2 and install it. That's it! Once you've installed the fix and rebooted your device iBooks should work just fine.