Schedules Jabber XMPP message for delivery.

    :param str message: text to send.
    :param list|str|unicode to: recipients addresses or Django User model heir instances with `email` attributes.
    :param User sender: User model heir instance
    :param int priority: number describing message priority. If set overrides priority provided with message type.

def schedule_jabber_message(message, to, sender=None, priority=None):
    """Schedules Jabber XMPP message for delivery.

    :param str message: text to send.
    :param list|str|unicode to: recipients addresses or Django User model heir instances with `email` attributes.
    :param User sender: User model heir instance
    :param int priority: number describing message priority. If set overrides priority provided with message type.
    """
    schedule_messages(message, recipients('xmppsleek', to), sender=sender, priority=priority)