phpCAS::setFixedCallbackURL PHP Méthode

    public static function setFixedCallbackURL($url = '')
    {
        phpCAS::traceBegin();
        phpCAS::_validateProxyExists();
        try {
            self::$_PHPCAS_CLIENT->setCallbackURL($url);
        } catch (Exception $e) {
            phpCAS::error(get_class($e) . ': ' . $e->getMessage());
        }
        phpCAS::traceEnd();
    }

 function setup()
 {
     //Only setup if we haven't already
     global $PHPCAS_CLIENT;
     if (!is_object($PHPCAS_CLIENT)) {
         phpCAS::setDebug("/var/www/campus/dev.intranet.campusforchrist.org/cas.log");
         phpCAS::proxy(SITE_CAS_VERSION, SITE_CAS_HOSTNAME, SITE_CAS_PORT, SITE_CAS_PATH, SITE_CAS_SESSION);
         phpCAS::setFixedCallbackURL(SITE_CAS_CALLBACK);
         //No SSL
         phpCAS::setNoCasServerValidation();
         phpCAS::setPGTStorageFile('xml', SITE_CAS_PGT_STORE);
         //session_save_path());
         return true;
     }
     return false;
 }