correct rDNS hostname & private IPs

Just revisiting this one again. I can now change my rDNS that resolves to a hostname, so that when a lookup is made the rDNS is correct.

At the moment if I have a domain using a private IP (as in Virtualmin 'private') when I do a lookup a warning will appear (such as: 'Warning - Reverse DNS does not match SMTP Banner'), as would be expected as the /etc/hosts file only has one record in it, that being the servername which resolves to the IP.

To resolve this, can I just add the private IP, and then a new hostname for the server ?

Thanks,

Paul