[SR-Users] Is there something like "silence detect hangup"

Problem - if connection drop, call can persist. In Asterisk there is silencedetecthangup - which should cause hangup, if there is full silence for desired period of time. Unfortunately it does not hangup. I mean: SIP client 1 ->Kamailio -> Asterisk ->Kamailio -> SIP client 2 If I drop connection for one of SIP clients, I expect call should be automatically hangup after a time I set (20 sec). But call persists. In worst case - if connection drops for both clients, call will persist until Asterisk is restarted. I will continue to look how to solve problem with Asterisk, but I am curious if this can be done from Kamailio also. If I can cancel call from both places - it will be great. I need to ensure that if something wrong happens, call will be dropped within 30 sec maximum. Stoyan