[Cialug] Hostname issue

[L. V. Lammert]

Trying to assist a friend in fixing an issue with their email system, ..
they appears to be using a Barracuda appliance (per hostname), yet it
appears to not be sending a valid hostname:

================

Nov 23 03:38:37 mx2 postfix/smtpd[5951]: NOQUEUE: reject: RCPT from
unknown[66.186.99.236]: 450 Client host rejected: cannot find your
hostname, [66.186.99.236]; from=<rhayden at gilstermarylee.com>
to=<lvl at omnitec.net> proto=ESMTP helo=<barracuda.gilstermarylee.com>

================

I do know they are switching providers, but I do not think that would
affect the issue. Any suggestion on how to troubleshoot this problem?

	TIA!

	Lee