code: public MessageBuffer<ChannelBuffer> getLoginBuffer(
  			InetSocketAddress localUDPAddress) throws Exception
  	{
  		ChannelBuffer loginBuffer;
  		ChannelBuffer credentials = NettyUtils.writeStrings(username, password,
  				connectionKey);
  		if (null != localUDPAddress)
  		{
  			ChannelBuffer udpAddressBuffer = NettyUtils
  					.writeSocketAddress(localUDPAddress);
  			loginBuffer = ChannelBuffers.wrappedBuffer(credentials,
  					udpAddressBuffer);
  		}
  		else
  		{
  			loginBuffer = credentials;
  		}
  		return new NettyMessageBuffer(loginBuffer);
  	}
docs: Creates the appropriate login buffer using username, password,
  connectionkey and the local address to which the UDP channel is bound.
  
  @param localUDPAddress
  <b>optional</b> If passed in, then this address is passed on
  to jetserver, so that it can associate this address with its
  session.
  @return Returns the ChannelBuffer representation of username, password,
  connection key, udp local bind address etc.
  @throws Exception