@signature
COMMAND: @signature <player> = <message>
ATTRIBUTE: Signature
Sets a message to be appended to every @mail message you send. It is appended directly at the end of the message, so if you wish to start the signature on a new line you should begin it with a %r.
Example:
@signature me=%rThis is a mail signature. (Note: You might want
to include the %r at the front of the signature, other wise it will be
combined with the @mail message.)