diff --git a/login/signup.php b/login/signup.php
index fdb73cc..0678d49 100644
--- a/login/signup.php
+++ b/login/signup.php
@@ -27,6 +27,7 @@
             $user->firstaccess = time();
             $user->secret = random_string(15);
             $user->auth = $CFG->auth;
+            $user = (object)truncate_userinfo ((array)$user);
             if (!empty($CFG->auth_user_create) and function_exists('auth_user_create') ){
                 if (! auth_user_exists($user->username)) {
                     if (! auth_user_create($user,$plainpass)) {