Problem with creation of a host record in DNS server

Hi, I have a problem when I try to create a host record in dns server. For example: if I create a host record namedserver-01, if I try to ping it with a pc in my domain, it responds. But if I try to ping it with a pc out of my domain, it's
unreachable. If I ping it with the domain suffix, server-01.mydomain.local, it works. I know that when I create a forward lookup zone its name is typically the same as the DNS suffix of the host computers for which you want to create the zone
(how explained here: http://support.microsoft.com/kb/323445), so I should create a zone without a name, so as I can ping the host name without adding the domain suffix. How can I solve this problem?

Thanks in advance.

Scorpion77