Surely posted before.. but wtf
You better be over lv 45, else the elite troll's will attack you, but it is possible, with a lv 1...
go to ZG, destroy your heartstone(or at least make sure its on cooldown), run agaist the portal(dont be in a party), auto unstuck, and Voila, you are in Old ZG, abit diffrent of normal ZG.
-Enjoy