Real time text (t140) and PJSIP

Is it possible to do t140 (Real Time Text) which the PJSIP channel driver? If not, can it be added? The invites are being OKed with port=0 for text portion of the SDP.

There is no such support, and someone has to write the code to do so.

Take a look this jira
https://issues.asterisk.org/jira/browse/ASTERISK-28654