Hi Rick,
It is possible to trigger transparent pass through of information on from one SIP dialog (representing 1 of the call legs)
to the other. Currently, transparency is limited to INVITE dialogs between 2 SIP Trunks. If SIP Line is involved, transparency is not supported. SUBSCRIBE dialogs, PUBLISH, out-of-dialog REFER, out-of-dialog unsolicited NOTIFY are not supported, and MESSAGE are not supported.
Please refer Supported Features for more details.
Thanks and Regards,
Geevarghese