private function _buildServerURI($path = 'challenge')
	{
	  	// Scheme
		$uri  = ( TRUE === $this->_ssl ) ? 'https://' : 'http://';
	  	// Host
		$uri .= self::RECAPTCHA_API_SERVER;
	  	// Path
		$uri .= ($path !== 'challenge') ? 'noscript' : $path;
	  	// Query
		$uri .= '?k=' . $this->_publicKey;
		$uri .= ($this->_error) ? '&error=' . $this->_error : NULL;
		$uri .= ( isset($this->_recaptchaOptions['lang']) ) ? '&hl=' . $this->_recaptchaOptions['lang'] : '&hl=' .$this->clientLang();

		return $uri;
	}