'Configure PLAIN authentication for a given domain.
PLAIN authentication uses a plain-text password file.
To cover all domains, use "*".
You can modify the password file at any time; it is reloaded automatically.'

def configure_plain(self, domain='*', passwords=None):

    if passwords:
        self.passwords[domain] = passwords
    self.log.debug('Configure    plain:    %s', domain)
