Hackers have found a way to enable the hidden ability in iOS 5 to make FaceTime calls over a 3G network. A guide is now available online for those who want to toggle it on.

By default, Apple’s iOS doesn’t allow users to place and / or receive FaceTime calls over any type of connection other than WiFi. But code tinkerers have now found a way to enable 3G support as well.

Unlike other hidden features that can be unlocked with a few steps, this one requires a jailbreak. Also note that it’s limited to the iPhone 4.

A guide is ready for those of you craving to make FaceTime calls over 3G, with instructions on what to download and what files to modify to enable the ability.