private static String getLocalServers(com.grey.logging.Logger logger) throws javax.naming.NamingException
	{
		javax.naming.directory.DirContext ctx = getDnsContext(null);
		java.util.Hashtable<?, ?> env = ctx.getEnvironment(); //NB: Does not return same object we passed into constructor
		ctx.close();
		Object providers = env.get(javax.naming.Context.PROVIDER_URL);
		logger.info(LOGLBL+"Default DNS servers ["+providers+"]");
		if (providers == null) return null;
		String[] serverspecs = ((String)providers).split(" ");

		for (int idx = 0; idx != serverspecs.length; idx++) {
			int pos = serverspecs[idx].indexOf(URL_DNS);
			if (pos != -1) serverspecs[idx] = serverspecs[idx].substring(pos + URL_DNS.length());
		}
		String servers = null;

		for (int idx = 0; idx != serverspecs.length; idx++) {
			if (serverspecs[idx] == null || serverspecs[idx].trim().length() == 0) continue;
			if (servers == null) {
				servers = serverspecs[idx];
			} else {
				servers = servers+" | "+serverspecs[idx];
			}
		}
		return servers;
	}