--- a/src/openttd.h	Fri Jun 22 10:57:53 2007 +0000
+++ b/src/openttd.h	Fri Jun 22 11:58:59 2007 +0000
@@ -59,6 +59,7 @@
 /* IDs used in Pools */
 typedef uint16 VehicleID;
 typedef uint16 StationID;
+static const StationID INVALID_STATION = 0xFFFF;
 typedef uint16 RoadStopID;
 typedef uint16 TownID;
 typedef uint16 IndustryID;