Sound the alarm - iOS 5 has already been jailbroken. The guys over at iPhone Dev-Team have put out a tethered jailbreak of Apple's latest offering. Hackers started working on the seventh beta version when it was released Sept. 12, a full month prior to Wednesay's official release date. This jailbreak requires Redsn0w to reboot and doesn't work with the latest devices - the iPhone 4S and the iPad 2 - but it does work on both versions of the iPod Touch, iPhone 3GS and 4, and the original iPad.

To avoid confusion, tethered jailbreaking requires a computer each time you have to reboot the OS (i.e., when you turn on your device, if your battery dies, etc.), while untethered jailbreaks allow you to reboot free of a computer after the initial activation on your device. Jailbreaking allows the user to alter the qualities of the OS in question, enabling customization and the installation of third-party apps not approved by the maker. Commenters on tech blogs have variously said that they used previous iOS jailbreaks to add features such as viewing weather conditions on the iPhone's home screen, using a device as a wi-fi tethering (different use of the term) hotspot, and customizing the look of their operating system.

While some Apple customers will be enthusiastically embracing the jailbreak, others don't see a need for it. Rahhb Riley, a commenter on Mashable, posted Thursday that with the new iOS 5, most of the features he usually installs with a jailbreak are already included.

For those with the inclination, instructions on how to perform the jailbreak have been posted at RedmondPie, and we're posting the instructional video here. If anyone has tried it, we'd love to hear your thoughts on it - please let us know in the comments section below.

Via Mashable, via RedmondPie