You may have heard news yesterday that Apple took measures to disable DRMed books on iBooks if you have a jailbroken device.
Well, we’ve heard that iPhone hacker extraordinaire Comex has come up with a fix for now:
1) Download the .deb file that Comex released: here
2) Install the .deb file
A) Connect your device to your computer you can SSH, or simply use iPhone Explorer (here), which lets you connect and view the files and folders within your device.
B) Go to the following folder: /var/root/Media/Cydia/AutoInstall and copy in that hunnypot.deb file.
Note that if Cydia and AutoInstall aren’t available, you can create them yourself, but it’s important to keep in mind that they are case-sensitive.
C) Reboot your device.
3) You’re done. You should now be able to read all your purchased books again.
It’s likely that the next jailbreak will have this fix built-in.