After some more investigation, my tech uncovered this information:
I just took a look. The problem is you are using UDP vs. TCP. Exchange only supports SIP over TCP.
Sample frame:
Frame 39 (853 bytes on wire, 853 bytes captured)
Ethernet II, Src: Buffalo_ae:ed:5a (00:0d:0b:ae:ed:5a), Dst: Vmware_65:98:0b (00:0c:29:65:98:0b)
Internet Protocol, Src: 204.11.192.22 (204.11.192.22), Dst: 192.168.11.6 (192.168.11.6)
User Datagram Protocol, Src Port: 5060 (5060), Dst Port: 5060 (5060)
Session Initiation Protocol
How do we make pbxnsip communicate over TCP?
Please advise.