diff --git a/distrib/utils/x_route/Makefile b/distrib/utils/x_route/Makefile
index bead5d3b3500..795de9ab7762 100644
--- a/distrib/utils/x_route/Makefile
+++ b/distrib/utils/x_route/Makefile
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile,v 1.6 1999/06/21 01:19:37 cgd Exp $
+#	$NetBSD: Makefile,v 1.7 2000/05/04 03:30:57 itojun Exp $
 #	@(#)Makefile	8.1 (Berkeley) 6/5/93
 
 PROG=	route
@@ -7,6 +7,9 @@ SRCS=	route.c show.c keywords.c
 
 SRCDIR= ${.CURDIR}/../../../sbin/route
 CPPFLAGS+= -DSMALL -I${SRCDIR}
+.if (${MACHINE_ARCH} == "i386") || (${MACHINE_ARCH} == "hpcmips")
+CPPFLAGS+= -DINET6
+.endif
 
 BINOWN=	root
 BINMODE=4555