Few days back, an untethered jailbreak of Corona was released enable the use of iBooks on untethered jailbroken devices. Later, a RedSn0w jailbreak tweak came to fix DRM issues with the Corona Jailbreak.
Now there is more good news for those who are using this untethered jailbreak tweak.
Shortly after, after the jailbreak tweak was updated to fix the DRM issues in iBooks, famous hacker Saurik tweeted that the untether has been updated yet again. This time the update aimed to resolve problems with the iPhone 4S running iOS 5.
If you have any problems with iBooks on your jailbroken device, you can install Corona directly from Cydia. If you have already installed Corona, you can just update it via Cydia.
Source: iDownload Blog