[Chicken_l33t]

//#CLIENTSIDE
function onPlayerenters(){
player.dir = dir (0 - up, 1 - left, 2 - down, 3 - right);
}

or for offline
//#CLIENTSIDE
if (playerenters){
playerdir = dir;
}

Replace "dir" with the number which is the direction you want e.g for up
playerdir = 0;