Greetings all,
I have a customer who currently has their domain name, ext DNS and
email hosted by Network Solutions. Let's call their company
COMPANY.COM.  They want NetSol to receive all email addressed to
<username>@COMPANY.COM and forward the email to their Exchange server
on their local network.  The internal forest/domain namespace is also
COMPANY.COM.  The reason for this request is if their Internet
connection goes down, NetSol will queue their mail until the Internet
connection is back online.

I am not quite sure how to configure this scenario.
Do I need to rename their internal DNS namespace to something like
COMPANYCORP.NET?
Do they need to purchase a second external domain (like COMPANY1.COM),
configure the Exchange for that name and forward the NetSol hosted
mailboxes for COMPANY.COM to COMPANY1.COM?  Please help.