Deactivate SIP Reason Header Field

Hi all!

I wonder if it’s possible to deactivate the SIP Reason Header Field feature, implemented in Asterisk after the approval of the RFC 3326.

A few months ago we used a PBX with an older Asterisk version, and when “A” called “B”, if “B” didn’t answer and the call was picked up by an extension “C”, “B” could see a missed call on the phone.

We actually have an Asterisk 1.8.20 PBX, whose version includes the SIP Reason Header Field feature, so missed calls are not shown when a call is picked up in other extension because of the “Call Completed Elsewhere” answer.

Users were used to see the missed calls even if they were answered elsewhere and now they are requesting me this, but I dont know if it’s possible.

Could you please help me?

Thanks in advance,
Best Regards.

David Bazaga.