if i use t_uac_dlg fifo command to send an invite request to a UAS that is behind NAT, t_uac sends ACK to the private contact address of 200 OK. in order fix the contact address in 200 OK, i should be able to somehow tell to t_uac_dlg that it should set a t_on_reply for the transaction. i didn't find any t_uac_dlg parameter for that purpose. perhaps there is some other way to get the contact address fixed? -- juha