FXO disconnect problem with PBX Ericsson BP 250

Answered Question
Jun 25th, 2008


I have connected a PBX ericsson BP 250 to an FXO in my voice enabled router 2811.

The problem is:

When an analog phone attached to the PBX calls an IP phone registred with the CME, the IP phone ring normally. But when the analog phone goes on-hook, the IP phone continues to ring.

Please can you help me.

Thank you very much.

I have this problem too.
0 votes
Correct Answer by Paolo Bevilacqua about 8 years 7 months ago

Hi, these should be CPTs for Tunisia:


Check if your PBX is actually using one of these.

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Overall Rating: 5 (1 ratings)
nizar.houichi Wed, 06/25/2008 - 01:41

Thank you very much mr Bevilacqua

I need to khnow this two parameters:



of the PBX BP-250

Thank you very much

Houichi Nizar

Paolo Bevilacqua Wed, 06/25/2008 - 01:57

Have tried OPX first ?

For the parameters, set cptone as per you country under voice port. That may be enough.

nizar.houichi Wed, 06/25/2008 - 02:14


I'm using extension. I call the number of port thet connect the PBX to the FXO. Then i dial the number of IP phone.

Tahnk you

Paolo Bevilacqua Wed, 06/25/2008 - 03:21

Then yes you need supervisory disconnect. If the default doesn't work, tell us which country are you in, record the tones with a PC and attach the file here.

nizar.houichi Thu, 06/26/2008 - 00:42


thank you first for your assistance.

I'm from tunisia and i use a pbx Ericsson BP 250

in a central office. I would like to khnow the parametres of this command:

voice class custom-cptone Discon

dualtone disconnect

frequency 425

cadence 500 500

Thank you very much.


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