asterisk users - Apr 2015 - Sending DTMF on not answered channel

Hello,

I setup a door open system with a basic DTMF card. The card is connected 
to an Sipura/Linksys 3102 FXS port and is powered by this port.

My problem is that when I send a call with Dial() command, channel has 
to be answered before receiving DTMFs, what my card does not. Is there a 
way to autoanswer those type of calls or to send DTMF on an non answered 
channel or another solution/idea to rich the goal ?

Only solution I found is to connect an analog phone in parallel to my 
card and to set it in autoanswer mode: at this moment the card get the 
DTMF sended via SendDTMF() command.

Thanks for any hint. Asterisk is 11.15.0 from Elastix 2.5

Regards

-- 
Daniel