Cannot transfer on IAX2 outgoing call


#1

I have a DIAL command simultaneously ringing both a SIP extension and my cellphone via an IAX2 terminating service provider. I am using the “t” option. If I answer from the SIP phone, I can hit the “#” and transfer the call. If I answer from my cell phone (going thru the pstn) the “#” is ignored. I would really like to be able to transfer calls from my cell phone. Is it a volume level problem? Inband vs. out of band? Any ideas?