Can you FaceTime between 2 iPhone 4s s over 4g?

Can you FaceTime between 2 iPhone 4s's over 4g?

The iphone4s is NOT a 4g phone

The iPhone 4S is technically not a 4G phone (and neither are all "4G" smartphones out there), but I will not needlessly go on about this.

Officially, not yet. You can't FaceTime a device that is not running on Wi-Fi unless the device(s) on a cellular network is/are jailbroken and has either made the appropriate file modifications or has a tweak like My3G or 3G Unrestrictor that tricks the phone into thinking it's on a Wi-Fi network. Once iOS 6 releases in October, FaceTime over cellular networks will be allowed on non-jailbroken iDevices.