No Disconnect message to Cisco5300 or Quintum DX

my connection :

Softphone(A)->Asterisk -->Cisco5300/Quintum–>TDM Switch -->Phone(B)

Problems are :when A hangup the call,the asterisk disconnect the call,but the Cisco/Quintum can’t recieve the hangup message

when B hangup the call,the Both party can disconnect the call…

May I know where the problems are ?