I still see some vestiges of that superstition today. When you visit some one's grave, you're always supposed to leave through a different gate then you entered. It is to trick the dead and make sure they don't follow you back home.
A most interesting tradition indeed. In Slovenia we don't have any documented vampire stories or superstitions despite the fact our folklore is well documented. Anyway do you folks think that this vampire superstition might be connected with old Serb practice of having graveyards in local forest? (that's what i have heard i am not sure how true is this)