diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 07c11fe0042..4d2e7978378 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -6814,7 +6814,7 @@ class emoticon_manager {
  * @return string The now encrypted data
  */
 function rc4encrypt($data) {
-    $password = 'nfgjeingjk';
+    $password = get_site_identifier();
     return endecrypt($password, $data, '');
 }
 
@@ -6827,7 +6827,7 @@ function rc4encrypt($data) {
  * @return string The now decrypted data
  */
 function rc4decrypt($data) {
-    $password = 'nfgjeingjk';
+    $password = get_site_identifier();
     return endecrypt($password, $data, 'de');
 }