DNS won't use Forwarder for some domain name

[cche]

I run NetWare 6.5 Sp5 DNS server for our domain i.e. domainA.com. It is setup to use my ISP name server as forwarder. We do have some parked domain name i.e. domainB.com and on the public DNS record, I have it redirected all the parked domain name to be forwarded to domainA.com and it is working fine from the Internet. However, in the internal network. When I did "nslookup domainB.com', I get "DNSsvrname.domainA.com can't find domain-b.com : The first online Indian business magazine Non-existent domain". However, it will find Google and NOVELL: Worldwide etc without problem.

In DNS, I only have domainA.com setup. The only other system that has domain name assigned is GroupWise 7. Is there a link between the two and how can I fix the problem?

Hope someone can help.

Thanks
Che