To improve performance, it should be possible for a client to read-ahead
messages when it does a receive.
i.e. when it does a receive the server actually sends a configurable
number of messages to the client in one request.
This has the advantage of reducing the number of requests between client and
server.
Similary, DUPS_OK acknowledgement needs implementing to reduce the
number of acknowledgement requests between client and server.
Regards,
Adrian