diff --git a/admin/webservice/script.js b/admin/webservice/script.js
index 8db3c012e62..a7d9f7a2f1c 100644
--- a/admin/webservice/script.js
+++ b/admin/webservice/script.js
@@ -1,12 +1,10 @@
 
 /* This function disable the valid until field of a user into service_users.php*/
-function disablevaliduntil(event, userid) {
+function external_disablevaliduntil(event, userid) {
    var disabled;
-   if (document.getElementById('enablevaliduntil'+userid).checked)
-   {
+   if (document.getElementById('enablevaliduntil'+userid).checked) {
        disabled = false;
-   }
-   else {
+   } else {
        disabled = true;
    }
    document.getElementById('menufromday'+userid).disabled = disabled;
diff --git a/admin/webservice/service_users.php b/admin/webservice/service_users.php
index 02877932712..e5ac7e87eae 100644
--- a/admin/webservice/service_users.php
+++ b/admin/webservice/service_users.php
@@ -191,7 +191,7 @@ if (!empty($allowedusers)) {
         $checkbox->text = get_string('enabled', 'webservice');
         $checkbox->label->text = get_string('enabled', 'webservice');
         $checkbox->alt = get_string('enabled', 'webservice');
-        $checkbox->add_action('change', 'disablevaliduntil', array($user->id)); //into admin/webservice/script.js
+        $checkbox->add_action('change', 'external_disablevaliduntil', array($user->id)); //into admin/webservice/script.js
         $contents .= $OUTPUT->checkbox($checkbox, 'enablevaliduntil');
         $contents .= ""; //init date selector disable status