diff --git a/memcache_storage.module b/memcache_storage.module
index d900e20..13880a8 100644
--- a/memcache_storage.module
+++ b/memcache_storage.module
@@ -138,6 +138,10 @@ function memcache_storage_init() {
 
     // Avoid caching of pages with debug info in external cache.
     drupal_add_http_header('Cache-Control', 'no-store, no-cache, must-revalidate, proxy-revalidate');
+
+    // Set the correct HTTP status code for "maintenance of the server" with 10 minutes as retry period.
+    drupal_add_http_header('Status', '503 Service unavailable');
+    drupal_add_http_header('Retry-After', 600);
   }
 }