diff -r 89570a8b6ed0 -r 143b0be22af1 src/newgrf_engine.cpp
--- a/src/newgrf_engine.cpp	Tue Nov 20 12:57:24 2007 +0000
+++ b/src/newgrf_engine.cpp	Tue Nov 20 13:35:54 2007 +0000
@@ -660,7 +660,7 @@
 			 *   bit 8: (Maybe?) Toggled whenever the train reverses.
 			 */
 
-			if (HasBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE)) SETBIT(modflags, 10);
+			if (HasBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE)) SetBit(modflags, 10);
 
 			return variable == 0xFE ? modflags : GB(modflags, 8, 8);
 		}