hello i need help on PSTN Calls via quintum gateway. i have a simple problem when i am try to send INVITE to PSTN quintum gw. it is replying me 183 session progress and call duration is starting at this point. after this he is sending ringing then 200 OK. Billseconds are incorrect in this case. UAC Asterisk GW 1|--INVITE->|---(invite)---------------->| 2|<--(183)--|<---(183 session progress)--| 3|<--(180)--|<---(180ringing)------------| 4|<--(200)--|<---(200 ok)----------------| 5|--(ACK)-->|---(ack)------------------->| 6|<-(med)-->|<---(media audio)---------->| i have problem in calculation of billseconds for CDR billseconds are starting from step 2 but it should be at step 5. Kamran Yahoo! Mail Stay connected, organized, and protected. Take the tour: http://tour.mail.yahoo.com/mailtour.html