--- a/src/aircraft_cmd.cpp	Fri Mar 16 17:40:31 2007 +0000
+++ b/src/aircraft_cmd.cpp	Fri Mar 16 21:42:11 2007 +0000
@@ -606,7 +606,7 @@
 
 	/* Check cargo */
 	CargoID new_cid = GB(p2, 0, 8);
-	if (new_cid > NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
+	if (new_cid >= NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
 
 	SET_EXPENSES_TYPE(EXPENSES_AIRCRAFT_RUN);
 

--- a/src/roadveh_cmd.cpp	Fri Mar 16 17:40:31 2007 +0000
+++ b/src/roadveh_cmd.cpp	Fri Mar 16 21:42:11 2007 +0000
@@ -1857,7 +1857,7 @@
 	if (v->type != VEH_ROAD || !CheckOwnership(v->owner)) return CMD_ERROR;
 	if (!IsRoadVehInDepotStopped(v)) return_cmd_error(STR_9013_MUST_BE_STOPPED_INSIDE);
 
-	if (new_cid > NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
+	if (new_cid >= NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
 
 	SET_EXPENSES_TYPE(EXPENSES_ROADVEH_RUN);
 

--- a/src/ship_cmd.cpp	Fri Mar 16 17:40:31 2007 +0000
+++ b/src/ship_cmd.cpp	Fri Mar 16 21:42:11 2007 +0000
@@ -1098,7 +1098,7 @@
 
 	/* Check cargo */
 	if (!ShipVehInfo(v->engine_type)->refittable) return CMD_ERROR;
-	if (new_cid > NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
+	if (new_cid >= NUM_CARGO || !CanRefitTo(v->engine_type, new_cid)) return CMD_ERROR;
 
 	SET_EXPENSES_TYPE(EXPENSES_SHIP_RUN);
 

--- a/src/train_cmd.cpp	Fri Mar 16 17:40:31 2007 +0000
+++ b/src/train_cmd.cpp	Fri Mar 16 21:42:11 2007 +0000
@@ -1744,7 +1744,7 @@
 	if (CheckTrainStoppedInDepot(v) < 0) return_cmd_error(STR_TRAIN_MUST_BE_STOPPED);
 
 	/* Check cargo */
-	if (new_cid > NUM_CARGO) return CMD_ERROR;
+	if (new_cid >= NUM_CARGO) return CMD_ERROR;
 
 	SET_EXPENSES_TYPE(EXPENSES_TRAIN_RUN);