diff --git a/example-dns-01-nsupdate-script.md b/example-dns-01-nsupdate-script.md
index 29ded88..a5f013c 100644
--- a/example-dns-01-nsupdate-script.md
+++ b/example-dns-01-nsupdate-script.md
@@ -28,6 +28,9 @@ case "$1" in
     "deploy_cert")
         # do nothing for now
         ;;
+    "unchanged_cert")
+        # do nothing for now
+        ;;
     *)
         echo Unkown hook "${1}"
         exit 1