def parse_recipients(header, reference_id=None):
    """\
    Returns the recipients of the cable as (maybe empty) list.
    """
    m = _TO_PATTERN.search(header)
    if not m:
        if reference_id and reference_id not in _CABLES_WITHOUT_TO:
            logger.warn('No TO header found in "%s", header: "%s"' % (reference_id, header))
        return []
    to_header = m.group(1)
    return _route_recipient_from_header(to_header, reference_id)