diff --git a/admin/automerge b/admin/automerge
index d54f6cb4ac6..7d71f290086 100755
--- a/admin/automerge
+++ b/admin/automerge
@@ -127,7 +127,11 @@ OPTIND=1
 [ "$test" ] && build=1
 
 
-tempfile=/tmp/$PN.$$
+if [ -x "$(command -v mktemp)" ]; then
+    tempfile=$(mktemp "/tmp/$PN.XXXXXXXXXX")
+else
+    tempfile=/tmp/$PN.$$
+fi
 
 trap "rm -f $tempfile 2> /dev/null" EXIT