Abstract: A method for providing presence gateway functionality includes deriving presence information for subscribers in a first set of subscribers based on telecommunications signaling messages. The first set of subscribers includes at least one subscriber who is not a subscribed-to presentity. The method also includes determining whether presence status information for a subscriber in the first set of subscribers has changed. In response to detecting a change in presence status, it is determined whether the subscriber is a subscribed-to presentity. If the subscriber is a subscribed-to presentity, a presence server is notified of the change in status of the subscriber.

Abstract: Methods and system for delivering presence information regarding push-to-talk subscribers are disclosed. In one method, a short message gateway receives presence information from a first push-to-talk subscriber from a presence or push-to-talk server. The short message gateway determines the location and availability of a second push-to-talk subscriber to which the presence information is directed. If the second push-to-talk subscriber is available, the SMS gateway delivers the presence information to the second push-to-talk subscriber in a manner that bypasses the SMSC. If the SMS gateway determines that the second push-to-talk subscriber is not available, the SMS gateway discards the presence information.