diff --git a/include/class.auth.php b/include/class.auth.php
index 400070ab420691769eaf158788a2da723c87a9c6..cca04f1df396e7e84a113957ef12083f10c1e0b4 100644
--- a/include/class.auth.php
+++ b/include/class.auth.php
@@ -636,6 +636,8 @@ class PasswordResetTokenBackend extends StaffAuthenticationBackend {
     }
 
     function signOn($errors=array()) {
+        global $ost;
+
         if (!isset($_POST['userid']) || !isset($_POST['token']))
             return false;
         elseif (!($_config = new Config('pwreset')))