public void processEvent(String event)
    {
        Document eventDoc = XMLUtils.toDocument(event);
        logger.log("processing event:\n" + eventDoc);
        try
        {
            JDOMResult matchesResult = new JDOMResult();
            synchronized (this)
            {
                matchTransformer.setParameter("EVENT", eventDoc
                        .getRootElement());
                matchTransformer.transform(new JDOMSource(patterns),
                        matchesResult);
                logger.log(matchesResult.toString());
            }

            Document matches = matchesResult.getDocument();
            logger.log(XMLUtils.toString(matches));

            XPath xpath = XPath.newInstance("/matches/match");

            @SuppressWarnings("unchecked")
            List<Element> matchesList = xpath.selectNodes(matches);

            logger.log("list:\n" + XMLUtils.toString(matchesList));

            for (Element match : matchesList)
            {
                Element response = new Element("response");
                String replyTo = match.getChildTextTrim("reply-to");
                String subject = match.getChildTextTrim("subject");
                response.addContent(match.cloneContent());

                logger.log("sending answer with subject \"" + subject
                        + "\" to " + replyTo);

                HttpHelper.doPost(replyTo, XMLUtils.toString(response));
            }

        }
        catch (Exception e)
        {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }