I've found a way to get behind the RFC portal without hacks. If it is a repost, please tell me and it will be deleted asap.
Behind RFC - Xfire Video
The "Beneath Orgimmar" hack was supposed to be fixed in WotLK. Well, the fix wasn't succesful, as you can see. There IS a barrier; all you have to do is to "run around" it. It requires 100% speed by the way.
Enjoy
:wave: