Those iPhone 4S owners suffering from buggy issues due to Apple's last update can take heart in the fact that iOS 6.1.2 is here. The over-the-air upgrade can now be downloaded on nearly any iOS device, but it's 4S users who needed it most.

Ever since the launch of iOS 6.1.1, iPhone 4S owners have reported a number of problems ranging from annoying to potentially crippling. For some reason, users attempting to sync their calendar service with Microsoft Exchange encountered problems significant enough for Microsoft to suggest that administrators either block or throttle iOS products until Apple addressed the issue.

Fortunately for those individuals, iOS 6.1.2 does tackle the problem; the update expressly states that it "fixes an Exchange issue that could result in increased network activity and reduced battery life."

What Apple doesn't mention in its description is the more serious security issues that cropped up when it last delivered an update. Those exploiting a specific bug in the phone's system could bypass a user's security passcode in order to gain access to the phone's contact list, voice mails and more. Apple doesn't specifically say they'd fix the bug, and iOS 6.1.2 doesn't mention the issue in its description, but many users were hoping the problem would be solved.

According the Ars Technica, however, the problem remains. The website attempted the very same exploit on its iPhone 4S after downloading 6.1.2 to find that it worked successfully. One of the site's commenters also confirmed that using complicated passcodes won't do anything to help, either. The long and short of it is that the update doesn't fix the problem, it's not clear when Apple will get around to it, and you should probably just keep a close eye on your phone.

While 6.1.1 was only available for iPhone 4S, iOS 6.1.2 can be downloaded on any iOS 6-enabled product. If downloading over-the-air won't work for whatever reason, you can access the upgrade through iTunes.