'Add a new MX record to this Zone.  See _new_record for
parameter documentation.  Returns a Status object.'

def add_mx(self, name, records, ttl=None, identifier=None, comment=''):

    ttl = (ttl or default_ttl)
    records = self.route53connection._make_qualified(records)
    return self.add_record(resource_type='MX', name=name, value=records, ttl=ttl, identifier=identifier, comment=comment)
