Do you think that the multiple-connection server (server_multi.bbc) would be of sufficient general interest to include it as an example program in a future release of BBC BASIC for SDL 2.0?
It doesn't have the two-way (chat) functionality of server.bbc, but that's only because of the inconvenience of determining which of the connections you are replying to.
I should add that it's fully compatible with BBC BASIC for Windows too, there's nothing BBCSDL-specific in the code, but since I'm not currently expecting to release a new version of BB4W its status as a possible example program there is moot.