Adding T38 to codec payload list

Hi guys

I have posted numerous entries to user forums, but I think this might be better put to the developers.

I want to use T.38 on my SIP gateways. They do this perfectly, but not when connected to Asterisk as it does not understand the codec so it does not allow the gateways to switch to T.38 when one encounters a fax machine.

I keep getting “Asterisk does not support t.38” replies in the user forums. However, Asterisk does not compile with G.723 codecs, or G.729 codecs (at least active), but it allows devices that wish to use these codecs talk to each other.

I suspect it is just a matter of adding the correct RTP payload to the codecs list.

Is it this easy and will it possibly get done in the near future?



If you want to work with me to get t38 working with me just give me a call at 1(507)379-0159. I havent got it working but am willing to try.

Did you finally find one solution ? Free or not ?
Please let me know.

thx :wink:

I got T.38 installed and works but locks up so the fax doesnt go through.


Thx for your answer.
What do you mean by ‘locks up’ ?

Could you tell me, what was configuration you made to allow T38 with SIP over Asterisk ?