1:1 NAT CT's behind PFsense do not receive emails from one another

[mudmanc4]

After searching for some time what I come up with is the need for split DNS !?

Although running kolab 3.x port 25 nor submission (587) cannot be accessed externally , which would account for the 4.4.1 error in sending email server.

Each public IP has a 1:1 NAT reserved DHCP to node CT's with the appropriate ports open as needed.

pfsense V-2.1 x86_64

Any guidance is appreciated.

Thanks, Rick