IPhone 4 - Facetime using 3G?

So, I'm really getting annoyed with apple now! I was happy to be informed that now we can use facetime through 3G instead of Wi-Fi so immediately updated my software. Now, upon trying to discover HOW exactly I do this I keep coming across jailbreak advice. I don't want to jailbreak my phone… And I didn't think apple did either. Surely if they're going to say that I can make 3G facetime calls - then I can? Does anybody know how I do this? Any apps or anything I have to change in my settings?

Ill appreciate it.

I'm not to sure on this since I don't have an iPhone. But I believe you should be able to just do it when you're on a 3G network. Just disable Wi-Fi on your phone and then try doing Facetime and it should attempt to use 3G instead.

Only on iphone 5 read the description on the software update page your only option jailbrake

Go to Settings->FaceTime and make sure you have mobile data turned on.

It's not just limited to the iPhone 5 like the other person said