In line with a report from last week, Apple has just released iOS 6.1.2. According to Apple, the update addresses a Microsoft Exchange bug but sources had indicated that it also addresses a lock screen passcode issue.
The update arrives as Build 10B146 for most devices, with the exception of cellular-capable iPad mini and fourth-generation iPad models that are receiving Build 10B147.Fixes and Exchange calendar bug that could result in increased network activity and reduced battery life.
Update: Users are reporting that the update does not in fact fix the passcode bug.
Article Link: Apple Releases iOS 6.1.2 to Address Exchange Calendar Bug