Player Z-tracking, again

code/game/turfs/space/space.dm

@@ -130,9 +130,12 @@
 		return
 
 	if(destination_z)
+		var/old_z = A.z
 		A.x = destination_x
 		A.y = destination_y
 		A.z = destination_z
+		if (old_z != destination_z)
+			A.onTransitZ(old_z, destination_z)
 
 		if(isliving(A))
 			var/mob/living/L = A