--- a/rail_cmd.c	Tue Jun 07 18:13:49 2005 +0000
+++ b/rail_cmd.c	Tue Jun 07 21:37:00 2005 +0000
@@ -374,7 +374,7 @@
 				break;
 			}
 
-			if ((m5 & 0xF0) == 0x10 && (m5 & 0x08 ? 1 : 2) == rail_bit)
+			if (IsLevelCrossing(tile) == 0x10 && (m5 & 0x08 ? 1 : 2) == rail_bit)
 				return_cmd_error(STR_1007_ALREADY_BUILT);
 			/* FALLTHROUGH */