Has anyone made this work? For me everything is fine until I switch canreinvite form no to yes. What happens is that asterisk hangs on "attempting native bridge" ... from what I understand "attempting native bridge" means that the RTP is routed through asterisk (just without any codec translation) But it shouldn't do that ... right? ... canreinvite is set to yes ... What's the best way to deal with this issue? I've also read that the only way to get the following situation ... UA --- NAT --- Internet --- NAT --- UA ... to work without passing the media path through asterisk is to use SER together with asterisk. Is that still true or was that because I was reading stuff from back in 2003? Some other discussions mention that canreinvite will simply not work with certain UAs .. is PAP2 one of those? .. Couple of other discussions that I've seen conclude that passing media stream UA-to-UA is just not practical when NAT is involved and is best to be avoided all together ... I'd like to make it work because it seems like a great way to save expensive server bandwidth. But if it will cause more trouble than it's worth then I will probably pass the media path through Asterisk and live with the fact that it will eat up my bandwidth. Also, IAX is superior when dealing with NATs , does it also handle UA-to-UA in NATed environment smoothly? What would be a good PAP2 alternative that uses IAX? This is my sip.conf: [1001] username=1001 type=friend secret=**** qualify=yes port=5060 nat=yes mailbox=1001@default host=dynamic dtmfmode=rfc2833 context=from-internal canreinvite=yes callerid="Test1" <1001> ... My PAP2 is configured with: STUN=yes STUN=stun.xten.net NAT Keepalive = 15 Outbound proxy = blank Proxy = IP of asterisk Any suggestions? Thank you, Tomas