This file gives a description of how AberMUDs can communicate with each other and the protocol used. I don't know of any implementation outside the Aber-community, but as usual I'm working on an LPC implementation for OuterSpace. The registration information should contain at least the name and IP address of your MUD, the port to use and a desired password. Aberchat communication is done via a TCP connection to a central intermud router.
Every message consists of a 'destination', a 'command' and 'parameters'.
This implies that this chacater is explicitly disallowed in the content of the arguments.