--- a/newgrf_engine.c	Sun Apr 30 18:41:16 2006 +0000
+++ b/newgrf_engine.c	Mon May 01 06:38:36 2006 +0000
@@ -416,7 +416,7 @@
 	res->ResolveReal   = &VehicleResolveReal;
 
 	res->vehicle.self   = v;
-	res->vehicle.parent = (v != NULL && v->type == VEH_Train) ? GetFirstVehicleInChain(v) : NULL;
+	res->vehicle.parent = (v != NULL && v->type == VEH_Train) ? GetFirstVehicleInChain(v) : v;
 
 	res->callback        = 0;
 	res->callback_param1 = 0;