'@param mailhost: A C{str} giving the mail exchange host which will
accept moderation emails from this server.  Must accept emails
destined for any address specified as a moderator.
@param sender: A C{str} giving the address which will be used as the
sender of any moderation email generated by this server.'

def __init__(self, filename, groups=None, moderators=(), mailhost=None, sender=None):

    self.datafile = filename
    self.load(filename, groups, moderators)
    self._mailhost = mailhost
    self._sender = sender
