DNS and Nslookup Problem

Here’s my problem. When I run Nslookup on my Windows XP machines it comes back with the following:

*** Can’t find server name for address 192.168.0.10: Non-existent domain
Default Server: pmgen01.pm
Address: 192.168.200.11

Basically, its not finding my DNS server and defaulting to a server that is used when using a VPN connections. How can I fix this to default to my DNS server (192.168.0.10) and why can’t it find the server name for 192.168.0.10??