2009/3/14 John kader <jado1977 at gmail.com>: > Hi all, Can anyone tell me please about which function should I use to reply > ACK to PSTN gateway after receiving a REINVITE? Hi John. Please review any SIP tutorial in which basic INVITE flow is explained. Basically, ACK is *not* a reply. Regards. -- Iñaki Baz Castillo <ibc at aliax.net>