This allows multiple instances with only one instance handling mail sends.

Changed mutex timeouts to INFINITE to hopefully eliminate reported "List index out of bounds" exceptions.

Removed unused code.

Added command prompt with menu (and single command right now: quit). :-)

Changed use of select to time out every 2 seconds (allows detection of closed server socket on Unix).

Generates a warning in the log (and the user's comment field) if the new user's IP address matches an existing user.

Guest logins are detected via blank password (rather than alias).
Guest's e-mail address is stored in netmail field.
User's hostname and IP address are stored in user record during login.
User's name is displayed during login.

Added "via telnet" when connection == 0xffff.
Added display of [C] when node has Local Chat (NODE_LCHAT) bit set.