Well this is different!!!
Just setup a Scalix box, using 192.168.1.200 as the IP. Their PIX firewall is 55.66.77.88 (as an example) and we tell the firewall that any port 25 traffic to that IP is to be forwarded to the 192.168 address. Works like a champ, Can login to SAC and webmail.
Now we register a FQDN (mail.thisplace.com) as 55.66.77.88
Can login to SAC using either the FQDN or the IP.
CAN'T login to webmail using either, keeps saying the username or IP is incorrect. And here's a real twist: go into SAC, change a user's password and set the flag that they have to change it on next login. They login into Webmail, it tells them their password needs to be changed and they change it, then it tells them it can't log them in because their username or password is incorrect!!!
Am I missing something here?? (using latest GA).