diff --git a/ChangeLog b/ChangeLog
index 09d5c1304..41d49f6b5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+20130220
+ - (tim) [regress/cipher-speed.sh regress/try-ciphers.sh] shell portability fix.
+
 20130219
  - OpenBSD CVS Sync
    - djm@cvs.openbsd.org 2013/02/18 22:26:47
diff --git a/regress/cipher-speed.sh b/regress/cipher-speed.sh
index 114191b89..21bf0f2e9 100644
--- a/regress/cipher-speed.sh
+++ b/regress/cipher-speed.sh
@@ -40,7 +40,7 @@ for c in $ciphers; do n=0; for m in $macs; do
 	case $c in
 	aes*-gcm@openssh.com)	test $n -gt 0 && break;;
 	esac
-	n=$(($n + 1))
+	n=`expr $n + 1`
 done; done
 
 ciphers="3des blowfish"
diff --git a/regress/try-ciphers.sh b/regress/try-ciphers.sh
index 87ec7497a..084a1457a 100644
--- a/regress/try-ciphers.sh
+++ b/regress/try-ciphers.sh
@@ -32,7 +32,7 @@ for c in $ciphers; do
 		case $c in
 		aes*-gcm@openssh.com)	test $n -gt 0 && break;;
 		esac
-		n=$(($n + 1))
+		n=`expr $n + 1`
 	done
 done