diff -r 4c9d49e5589a src/engine.cpp
--- a/src/engine.cpp	Mon Dec 08 16:29:36 2008 +0000
+++ b/src/engine.cpp	Tue Dec 09 23:27:50 2008 +0100
@@ -72,6 +72,8 @@ Engine::Engine(VehicleType type, EngineI
 	if (base >= _engine_counts[type]) {
 		/* Mark engine as valid anyway */
 		this->info.climates = 0x80;
+		/* Set model life to maximum to make wagons available */
+		this->info.base_life = 0xFF;
 		return;
 	}
 
@@ -86,6 +88,10 @@ Engine::Engine(VehicleType type, EngineI
 			this->u.rail = _orig_rail_vehicle_info[base];
 			this->image_index = this->u.rail.image_index;
 			this->info.string_id = STR_8000_KIRBY_PAUL_TANK_STEAM + base;
+
+			/* Set the default model life of wagons to the maximum (usually infinite) */
+			if (this->type == VEH_TRAIN && this->u.rail.railveh_type == RAILVEH_WAGON) this->info.base_life = 0xff;
+
 			break;
 
 		case VEH_ROAD:
@@ -264,7 +270,7 @@ void StartupEngines()
 
 		e->reliability_spd_dec = ei->decay_speed << 2;
 
-		if (IsWagon(e->index)) {
+		if (IsWagon(e->index) && ei->base_life == 0xff) {
 			e->age = 0xFFFF;
 		} else {
 			CalcEngineReliability(e);