IP phone outbound call - ISDN problem?

[v.srsen]

We have a Call Manager 3.3(3) with 60 IP Phones 7940/60. Voice gateway to the PSTN is 3745 with 2 PRI ISDN links to the telecom provider. Call control protocol is MGCP. We have a problem with outbound calls: if we have an outbound call from an IP phone to a phone on a PSTN, and if the called party (PSTN phone) hangs up, the call is not disconnected on IP phone. On ISDN Q931 debug we see that our voice gateway gets only the NOTIFY message from the PSTN. Only after we hang up the IP phone, the call is disconnected and a DISCONNECT message is received.

Has anyone got an idea what might be the problem?

We don't have this situation with inbound calls.

P.S. I don't know if there could be a connection, but CCM and IP phones are part of the IPCC call center, but this situation is happening regardless of this fact, when phones are not used by any agent.

Thanks in advance

[irisrios]

It seems to be problem with Callmanager configuration.

You can try

1) Enabling 'isdn sending-complete' IE in the outgoing call Setup.

2) Go to Service -> Service parameters -> Select your server -> Select 'Cisco Callmamager Service' -> Select parameter 'SendingCompleteIndicator' change the value to 'True', click update.

[v.srsen]

It doesn't help...I have the same CallManager configuration at another customer and I don't have this problem, the call disconnects regularly...

I presume that the problem is at the telecom's LCE...?