public function setStreamContext($context)
    {
        if (!is_resource($context) || get_resource_type($context) !== "stream-context") {
            /**
             * @see Zend_Soap_Client_Exception
             */
            require_once "Zend/Soap/Client/Exception.php";
            throw new Zend_Soap_Client_Exception(
                "Invalid stream context resource given."
            );
        }

        $this->_stream_context = $context;
        return $this;
    }