protected function _initVarnishPool()
    {
        $this->pool = new VarnishPool();

        $addresses =  Mage::getStoreConfig(self::XML_PATH_VARNISH_SERVER);
        $secret = Mage::getStoreConfig(self::XML_PATH_VARNISH_SECRET);

        if (Mage::getStoreConfigFlag(self::XML_PATH_VARNISH_SECRET_NEWLINE)) {
            $secret .= "\n";
        }
        
        $lines = explode("\n", $addresses);
        $instantiated = array();
        foreach ($lines as $line) {
            $line = trim($line);
            
            if (!preg_match('/^[a-z0-9_\-\.]+:\d+$/', $line)
                || isset($instantiated[$line])) {
                continue;
            }
            
            list($host, $port) = explode(':', $line);

            try {
                $this->pool->addServer(new VarnishAdmin($host, $port, $secret));
            } catch (VarnishException $e) {
                Mage::logException($e);
            }

            $instantiated[$line] = true;
        }

        $this->pool->setIgnoreOnFail(true);

        return $this;
    }