MWI signal from Unity 4.0(3) cannot be passed across Nortel PBX Tandem

[raymond.lai]

My client has a set of Unity 4.0(3) with failover with off-box Exchange as the message store. The Unity is integrated with Nortel PBX using the PBXlink. Everything is working fine including the MWI for the Nortel phones located at the same site as the Unity system.

However, my client's company has different locations and each location has one set of Nortel PBX system. THese PBX systems are interlinked with each other somehow.

Now my client discovers that there is the Voice Mail for Nortel Phones located at different site from the Unity system, when the Unity system is sending the MWI signal to the digital lines connecting with Nortel PBX through the PBXlink, it seems that these MWI signals cannot pass across different/multiple Nortel PBX and the MWI lights on those remote Nortel phones cannot be turned on.

My client would like to know how Unity system can support or send MWI signal across the Nortel PBX / Tandem system?

Cheers,

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Raymond CB Lai

[eschulz]

This is probably something that needs to be researched on the Nortel side. With centralized voicemail in general, Nortel or otherwise, the inter-PBX networking should be transparent to the voicemail system. i.e. from the message center's perspective the phone system network should appear as one giant PBX.

The Nortel documentation I've seen has been pretty detailed regarding system requirements for MWI internetworking. It is unlikely that I can offer specific help for your client's particular systems. However, I would expect that digital trunks (ISDN) between nodes are a minimal requirement.

Regards,

Eric

[raymond.lai]

Hi Eric,

Thanks for your input. In fact, my client has checked out something from PBX side and after changing the parameters, the problem is fixed.

THe Cisco document asks us to configure 1 pilot number as the ACD number on Nortel PBX. Under this ACD number, there are 48 analog numbers for answering the calls towards Unity. It is that "ACD" number that causes the problem on the Nortel side.

WHat my client did was to change the type of this "ACD" number into the type called "Message Center type". This is the type that Nortel PBX are using to pass the MWI signal among them. After changing this parameter, the MWI signals can be passed in between PBX system.

Eric, do you have any idea of that as my client would like to know if this is also the official or recommended approach to do this change as this change is not the same as recommeneded by Cisco document.

Cheers,

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Raymond