--- a/rail_cmd.c	Tue Nov 07 22:34:59 2006 +0000
+++ b/rail_cmd.c	Tue Nov 07 23:25:27 2006 +0000
@@ -285,7 +285,7 @@
 			/* XXX Assume a 'higher' railtype has preference. This means we
 			 * will convert from normal rail to electrified rail, but not
 			 * the other way around. */
-			if (GetRailType(tile) < p1) {
+			if (GetRailType(tile) < (RailType)p1) {
 				ret = DoCommand(tile, tile, p1, flags, CMD_CONVERT_RAIL);
 				if (CmdFailed(ret)) return ret;
 				cost += ret;