Or instead of not creating the record you can always create the record pointing to 127.0.0.1
But as katsklaw said it is impossible to create a fake DNS to keep real IP's secure because by doing so you leav your clients with NO server IP's to connect to.
Personally in my dns ive set services, stats and hub to 127.0.0.1, all my other servers (because theyre used so clients can connect) are set to their correct IP.
And before you suggest having the DNS return a fake IP unless it's an IRC client looking it up, the DNS server has no way to tell what program is looking up the host.