cannot find my internet domain

[Hakki Aydin Ucar]

Fedora core 7 based DNS server is working for external domains via
dig, nslookup etc.
But when i issue the command nslookup or host or dig i got the following error:

[root at dns ~]# nslookup  www.servisnet.com.tr
;; connection timed out; no servers could be reached

Servisnet.com.tr our domain name,

is it normal behavior or I have lack of configuration ?