If the node is configured to support the "pubsub#notify_sub" option, the service MUST send to the node owners notifications regarding new subscribers, SHOULD send notifications regarding unsubscribe actions, and MAY send notifications regarding other subscription changes. The relationship between these notifications and the retrieval of the subscriptions list as described under Retrieve Subscriptions List is similar to the relationship between a "roster get" and a "roster push" as described in &xmppim;.
-In particular, the notification consists of a &MESSAGE; stanza containing a <pubsub/> element qualified by the 'http://jabber.org/protocol/pubsub#owner' namespace, which contains a <subscriptions/>l element whose 'node' attribute specifies the NodeID of the relevant node; this <subscriptions/> element in turn contains one <subscription/> element whose 'jid' attribute specifies the address of the subscriber and whose 'subscription' attribute specifies the suubscription state.
-For instance, the following example shows a new subscriber notification.
-The following example shows an unsubscribe notification.
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