TestPassCmdHandler handler = new TestPassCmdHandler();
handler.add("valid", new MockMailbox(identifier, MESSAGE1, MESSAGE2));
server = new NettyServer(createProtocol(handler));
server.setListenAddresses(address);
server.bind();
POP3Client client = new POP3Client();
client.connect(address.getAddress().getHostAddress(), address.getPort());
assertTrue(client.login("valid", "valid"));