Hey Joe,
your solution doesn't work for my Workcentre 6515DNI, I still get the DNS server un-sets up in SMTP Error.
You find the Xerox configuration in the screendumps (1. WLAN, 2. SMTP, 3. DNS).
The printers Ip is static and assigned to xerox.local in my hosts file.
Do I need to make any changes in my FritzBox?
Thanks
Joko