Abstract: A method and system for preventing hung calls on a channel of a network interface device of a voice messaging system is described. A channel of the network interface device receives a new incoming call from the telephone network. If no other call is in progress on the same channel as the one on which the new call was received, the new incoming call is accepted. On the other hand, if another call is already in progress on this channel, the other call is terminated and the new incoming call is rejected. At this point, the network interface device is ready to accept any subsequent calls received on that channel.

Abstract: A “high availability” telephony/messaging system includes a first host comprising a first telephony application, a second host comprising a second telephony application, and a TSP for routing calls on a plurality of telephone circuits to the first and second hosts, for processing by one of the first and second applications. An Inter-System Call Transfer process permits a call routed to an application on one host to be transferred to an application on another host. Therefore, a call routed to a host that is unable to process the call can be redirected to another host that is able to process the call.