And in this article I would like to share the fix for iBook crashes hopefully it works for you, so you can continue using this wonderful app for your daily need.
Update: install Corona 1.0-4 to fix iBooks crash or the better version Corona 1.0-5 with reboot forcing after installed the package.
How to fix iBooks crashing after iOS 5.0.1 untethered jailbreak
1.Add this url repository in Cydia : repo.insanely.com, then install iBookFix2 from this repo.
2. Respring the iDevice.
3. When the springboard crashes, go in safe mode then.
4. Reboot your iPhone.
5. Hope it works. (MacRumors)
If the above failed, then try this:
1. Download this deb file,
2. SSH in your device and add this folder /var/root/Media/Cydia/AutoInstall. In case you don't have that folder, create it then!
3. Restart your device. (iDownloadBlog).