diff --git a/git-remote-gcrypt b/git-remote-gcrypt
index 6f6a009..9dce8ec 100755
--- a/git-remote-gcrypt
+++ b/git-remote-gcrypt
@@ -40,6 +40,12 @@ isurl() { isnull "${2%%$1://*}"; }
 
 xgrep() { command grep "$@" || : ; }
 sort_C() { LC_ALL=C command sort "$@"; }
+sort_stable_k2()
+{
+	awk '{ printf("%08d %s\n", NR, $0) }' | sort_C -k3,3 -k1,1 |
+		awk '{ print $2 " " $3 }'
+}
+
 tac() { sed '1!G;h;$!d'; }
 
 # Split $1 into $prefix_:$suffix_
@@ -437,8 +443,7 @@ do_push()
 $1
 EOF
 
-	# POSIX compat issue: sort -s (stable), but supported in bsd and gnu
-	Branchlist=$(xecho "$Branchlist" | sort_C -k2 -s | tac | uniq -s40)
+	Branchlist=$(xecho "$Branchlist" | sort_stable_k2 | tac | uniq -s40)
 
 	TmpPack_Encrypted="$Localdir/tmp_pack_ENCRYPTED_.$$"
 	TmpObjlist="$Localdir/tmp_packrevlist.$$"