Apple has released iOS 6.1.3 beta 2 to developers for iPhone, iPad, and iPod touch. The first beta was known as iOS 6.1.1 beta 1, but it has been renamed to iOS 6.1.3 due to the recent public releases of iOS bug fix updates.
As we previously covered, iOS 6.1.3 includes several enhancements to the Maps application for Japan. Notably, the upcoming iOS 6.1.3 update will also fix the recently publicized Lock Screen bug, according to Apple.
It is also possible that the update plugs the exploits used in recent jailbreaks, but we have not verified that.