diff --git a/build.sh b/build.sh
index 4a6748bfbeb7..7caef96b9dbb 100755
--- a/build.sh
+++ b/build.sh
@@ -1,5 +1,5 @@
 #! /usr/bin/env sh
-#	$NetBSD: build.sh,v 1.204 2009/03/06 16:29:40 apb Exp $
+#	$NetBSD: build.sh,v 1.205 2009/03/09 06:25:51 apb Exp $
 #
 # Copyright (c) 2001-2009 The NetBSD Foundation, Inc.
 # All rights reserved.
@@ -178,7 +178,7 @@ initdefaults()
 	uname_m=$(uname -m 2>/dev/null)
 	uname_p=$(uname -p 2>/dev/null || echo "unknown")
 	case "${uname_p}" in
-	''|unknown|*[^a-z0-9]*) uname_p="${uname_m}" ;;
+	''|unknown|*[^-_A-Za-z0-9]*) uname_p="${uname_m}" ;;
 	esac
 
 	id_u=$(id -u 2>/dev/null || /usr/xpg4/bin/id -u 2>/dev/null)
@@ -1213,7 +1213,7 @@ createmakewrapper()
 	eval cat <<EOF ${makewrapout}
 #! ${HOST_SH}
 # Set proper variables to allow easy "make" building of a NetBSD subtree.
-# Generated from:  \$NetBSD: build.sh,v 1.204 2009/03/06 16:29:40 apb Exp $
+# Generated from:  \$NetBSD: build.sh,v 1.205 2009/03/09 06:25:51 apb Exp $
 # with these arguments: ${_args}
 #
 
diff --git a/share/mk/bsd.own.mk b/share/mk/bsd.own.mk
index 6ac49068afe4..d8f2d943c60f 100644
--- a/share/mk/bsd.own.mk
+++ b/share/mk/bsd.own.mk
@@ -1,4 +1,4 @@
-#	$NetBSD: bsd.own.mk,v 1.558 2009/03/06 16:29:41 apb Exp $
+#	$NetBSD: bsd.own.mk,v 1.559 2009/03/09 06:25:51 apb Exp $
 
 .if !defined(_BSD_OWN_MK_)
 _BSD_OWN_MK_=1
@@ -128,7 +128,7 @@ _HOST_OSREL!=	uname -r
 # For _HOST_ARCH, if uname -p fails, or prints "unknown", or prints
 # something that does not look like an identifier, then use uname -m.
 _HOST_ARCH!=	uname -p 2>/dev/null
-_HOST_ARCH:=	${HOST_ARCH:tW:C/.*[^a-z0-9].*//:S/unknown//}
+_HOST_ARCH:=	${HOST_ARCH:tW:C/.*[^-_A-Za-z0-9].*//:S/unknown//}
 .if empty(_HOST_ARCH)
 _HOST_ARCH!=	uname -m
 .endif