P-Dual-Info Header
When the Oracle® Enterprise Session Border Controller forward both media DTMF indication and signaling based DTMF indication for the same received DTMF indication, a P-Dual-Info header is added to the forwarded signaling message. You can configure the appearance of the header with the dual-info option. The default header appearance is:
P-dual-info: true
P-Dual-Info headers are only inserted into SIP INFO messages.