diff --git a/sys/conf/Makefile.kern.inc b/sys/conf/Makefile.kern.inc
index 4b45382525a4..6663b15c8103 100644
--- a/sys/conf/Makefile.kern.inc
+++ b/sys/conf/Makefile.kern.inc
@@ -1,4 +1,4 @@
-#	$NetBSD: Makefile.kern.inc,v 1.90 2006/10/26 05:10:55 thorpej Exp $
+#	$NetBSD: Makefile.kern.inc,v 1.91 2006/10/30 17:56:30 garbled Exp $
 #
 # This file contains common `MI' targets and definitions and it is included
 # at the bottom of each `MD' ${MACHINE}/conf/Makefile.${MACHINE}.
@@ -74,7 +74,7 @@ CWARNFLAGS+=	-Wcast-qual -Wwrite-strings
 CWARNFLAGS+=	-Wno-sign-compare
 . if ${HAVE_GCC} > 3
 CWARNFLAGS+=	-Wno-pointer-sign -Wno-attributes
-.  if ${MACHINE} == "i386" || ${MACHINE_ARCH} == "sparc64" 
+.  if ${MACHINE} == "i386" || ${MACHINE_ARCH} == "sparc64" || ${MACHINE} == "prep"
 CWARNFLAGS+=	-Wextra -Wno-unused-parameter
 .  endif
 . endif