Thank you.
Some H.323 endpoint use in-band signalings method such as NetMeeting, while other endpoint such as Polycom PVX use rfc2833 to transfer DTMF. But I don't know how get DTMF info from PVX's audio RTP packets. The code rfc2833.cxx in h323plus seems can not work with PVX.
Hello bian
the uso of tones, and other in-band signalings depends of the CODEC support, u must read the documentation about the codec u are using if suport in-band signaling. for example
G.729 dont suport in-band tones and fax.
tip:
http://en.wikipedia.org/wiki/G.711 (at botton of page are the others G7xx.x)