And the news was brought by Pod2G recently on Twitter, and thanks to PlanetBeing for finding fix on Corona issue with iBooks DRMd books. And will be releasing Corona 1.0.6 soon.
Albeit it is not the first update, previously Corona 5.0.1 version 1.0-5 was released. Yet the widely known issue for jailbroken issue which is iBooks crash unable to be solved.
And if this is your first time hearing the name Corona, Corona is untethered jailbreak tool for iPhone 4 running on iOS 5.0.1 firmware developed by Chronic Dev Team based on Pod2G exploit. And the tool can be installed from Cydia -- this is a guide to install Corona via Cydia.