@Override
    public Element getSubsriptionErrorDetail() {
        return DocumentHelper.createElement(QName.get("presence-subscription-required",
                "http://jabber.org/protocol/pubsub#errors"));
    }
Anyone with a presence subscription of both or from may subscribe and retrieve items.

@author Matt Tucker
xmppserver/src/main/java/org/jivesoftware/openfire/pubsub/models/PresenceAccess.java