Regular expressions in DNS?

[Zach]

I have some VPS clients and I would
like to begin giving them pretty reverse
DNS records when they first sign up -
like
ip-255-255-255-255.vps.niftyhost.us -
that resolve both backwards and
forwards via an A record or similar. The
only way I can imagine doing this is by
manually creating separate A records
for every domain. I was checking out
NAPTR earlier, but it looked to be only
for SIP.
Is there any way to use regexp in DNS?