This glitch is simple, in just about any building with an in-accessible room, a player can run and vault into the door (and or wall) and make their way into that room that is not normally accessible. I and my clan have been getting killed from what seemed to be "invisible" players. They would log off in said room and server hop until they found their prey, wait until their backs are turned and then jump out of the room killing us. A good example of this is in the prisons on the airfields. In the room directly in front of the door. If you are in that room you can see the entire contents of the building as if the walls were invisible. During my short time of server hopping in the rooms looking for the exploiters to see if this was the method they were using i have ran into 2 individuals. Confirming my hypothesis.