A method for indicating the presence of a text message in a mobile radiotelephone network if the recipient is registered as a subscriber both in the mobile radiotelephone network and in another communication network as a subscriber. It is provided that the availability of the subscriber in the other...http://www.google.ca/patents/US6351648?utm_source=gb-gplus-sharePatent US6351648 - Method for indicating that a text message is present in a message central module of a mobile radiotelephone network
