diff --git a/webservice/externallib.php b/webservice/externallib.php
index 8391df7b68f..7167b3c72b9 100644
--- a/webservice/externallib.php
+++ b/webservice/externallib.php
@@ -77,6 +77,7 @@ class core_webservice_external extends external_api {
                       array('serviceshortnames'=>$serviceshortnames));
 
         $context = context_user::instance($USER->id);
+        $systemcontext = context_system::instance();
 
         $userpicture = new user_picture($USER);
         $userpicture->size = 1; // Size f1.
@@ -84,7 +85,7 @@ class core_webservice_external extends external_api {
 
         // Site information.
         $siteinfo =  array(
-            'sitename' => $SITE->fullname,
+            'sitename' => external_format_string($SITE->fullname, $systemcontext),
             'siteurl' => $CFG->wwwroot,
             'username' => $USER->username,
             'firstname' => $USER->firstname,