Creates a 307 "Temporary Redirect" response including a HTTP Warning
        header with code 299 that contains the user message received during
        processing the request.

def create_307_response(self):
        """
        Creates a 307 "Temporary Redirect" response including a HTTP Warning
        header with code 299 that contains the user message received during
        processing the request.
        """
        request = get_current_request()
        msg_mb = UserMessageMember(self.message)
        coll = request.root['_messages']
        coll.add(msg_mb)
        # Figure out the new location URL.
        qs = self.__get_new_query_string(request.query_string,
                                         self.message.slug)
        resubmit_url = "%s?%s" % (request.path_url, qs)
        headers = [('Warning', '299 %s' % self.message.text),
#                       ('Content-Type', cnt_type),
                   ]
        http_exc = HttpWarningResubmit(location=resubmit_url,
                                       detail=self.message.text,
                                       headers=headers)
        return request.get_response(http_exc)