Dtmfmode=info and voicemail

According to voip-info.org/wiki/view/Aste … p+dtmfmode

dtmfmode=info does not work with Asterisks voicemail

Is it still true?

My SIP-adapters have rfc2833 implemented in a manner which Asterisk doesn’t like. I’ve tryed to use inband on the phone side and rfc2833 on the SIP trunk side but this does not work - Asterisk in not translating the tones. I’m looking for a solution which will work with local Asterisk VM as well as with provider’s VM.

It seems that I have to answer my own question :wink:

dtmfmode=info does work with Asterisks voicemail, as soon as SIP UA is using appropriate SIP INFO message format.

Old good PAP2 (works fine):

Message Header
Content-Type: application/dtmf-relay

Message body

VTech ip8100, PAP2 v2 and their brothers (Asterisk reports 415 Unsupported media type):

Message Header
Content-Type: application/text

Message body

It will be nice if it will be possible to patch Asterisk to parse those messages in more relaxed manner.