If you are a VPS or dedicated server client you can request
reverse DNS (rDNS, PTR) changes via our helpdesk.
If your account is a shared or reseller account we will not be
able to setup reverse DNS. This has no affect on the usage of
your account (including email) and we do not setup rDNS on
all IP numbers for administration reasons.
The main reason for requiring accurate rDNS entries is so
that email communication will work properly with some major
ISP's such as AOL. All email originating from our servers uses
the main server IP when communicating with other servers
(regardless of whether the account uses a dedicated IP or
not). The main IP of all servers have rDNS setup so that
email communication is not affected.