public function start(array $options = array())
    {
        if ($this->isStarted() === false) {
            // Cookie parameters must be defined before session_start()!
            if (!empty($options)) {
                $this->setCookieParams($options);
            }

            if (!session_start()) {
                return false;
            }
        }

        // Reference is important! Because we are going to deal with $_SESSION itself
        // not with its copy, or this simply won't work the way we expect
        $this->session =& $_SESSION;

        // Store unique data to validator
        $this->sessionValidator->write($this);

        return true;
    }