The news was brought by Pod2G on his recent blog's post saying he will bring update to Corona , after this iBooks issue is entirely solved.
A guy namely @xvolks, xBooks developer, is said to helps patching the kernel in the Corona tool to bring iBooks back to work.
The reason of iBooks crashing is because Apple has placed this built to the application bundle to fight jailbreaking activity. But since we have bought the application means we can use it whether our device is jailbroke or not. But Apple thinks otherwise, ouch! Fortunately once the update is released we can use it again properly.
Aside fixing iBooks crash, the update will be fixing another applications that are reported have sandbox issues.
And judging the situation we can expect the release of the Corona update relatively soon. Therefore before the A5 untethered jb release, all of us already own devices with free iBooks crash.
To install the upcoming Corona package can be performed via Cydia (see the tutorial to get Corona on Cydia), or if your iPhone has not been jailbroke yet, then jailbreak it using Redsn0w 0.9.10b3.
Update: Install Corona 1.0-4 to fix iBooks crash or install the stabler version Corona 1.0-5.