DNS & ACTIVE DIRECTORY

Hi,

I have just installed a windows 2000 with Active directory and setup DNS on the server & the IP address is say 172.16.8.1. I have also installed DHCP,WINS on this server.

I have a leased line to the internet. My ISP have given me 2 DNS numbers for the internet access which i added in the TCP/IP settings.

The problem is this.

I cannot browse the internet and internal network at the same time.If i set the external DNS info as the preferred DNS,then i can connect
to the internet- no lan browsing.
If i change the DNS to local DNS then i can’t connect to the internet.

How can i resolve this ?

Thanks.

Charles.

Clouis2000@yahoo.com