The RedSn0w jailbreak tool has been updated to version 0.9.10b5, that promises to fix iBooks DRM problems. This fix that has been integrated into RedSn0w, developed by PlanetBeing apparently sorts out the issues of the jailbreak detection by iBooks, that in some cases causes images not to display in the proper manner.
Please do let us know if you are having problems with iBooks on your jailbroken device? If this is the case, then running the new RedSn0w update on top of your existing jailbreak is an option even though you could wait for the upcoming Corona update.
If you do decide to run RedSn0w, you must make sure you do not select Cydia, the Dev Team mentions that if auto-detection fails and redsn0w prompts the no identifying data was found message, you may want to try pre-select the appropriate 5.0.1 IPSW using “Extras->Select IPSW”.
You can choose not to use RedSn0w jailbreak and wait for the Corona 1.0-6 update, which will also have the iBooks fix.
For more information and downloads, please visit iDB as they have the full details. As usual we always ask you, if you try out this new update please let us know how you got on.