diff --git a/modules/update/update.fetch.inc b/modules/update/update.fetch.inc
index a3af87f7b3b..7a3a9765ebe 100644
--- a/modules/update/update.fetch.inc
+++ b/modules/update/update.fetch.inc
@@ -28,9 +28,7 @@ function _update_refresh() {
 
   $available = array();
   $data = array();
-  $site_key = '';
-  $drupal_private_key = variable_get('drupal_private_key', '');
-  $site_key = md5($base_url . $drupal_private_key);
+  $site_key = md5($base_url . drupal_get_private_key());
   $projects = update_get_projects();
 
   foreach ($projects as $key => $project) {