Patent ID: 7899478

Claim:
A push to talk server for forwarding push to talk messages in a mobile radio network, the server comprising an interface for receiving, from push to talk clients, requests to send push to talk messages; an interface for receiving push to talk messages to be forwarded; an interface for transmitting push to talk messages to push to talk clients; an interface adapted to receive messages to be transmitted to push to talk clients from another server; an interface adapted to transmit push to talk messages, received from push to talk clients, to said another server; and a granting mechanism for granting, to one push to talk client at a time within a push to talk group, permission to send push to talk messages, the push to talk server comprising: an interface adapted to receive a request from said another server to send messages to push to talk clients via the push to talk server; wherein the granting mechanism is adapted to handle the request from said another server in a manner so that no more than one of a push-to-talk client or said another server is permitted to send messages to push to talk clients within an enlarged chat group at a time; and the push to talk server is adapted to respond to a request from said another server in a different manner than to a request from a push to talk client.