VPN Using Wrong DNS Server

[dln]

I'm having a problem with which DNS server our client machines use that
perhaps someone can help me with. All of our site's laptops run Windows XP
and, when on site, connect to our domain via a physical Ethernet link. When
traveling, the laptops connect to our site via a VPN connection. The VPN
connection is normally made over a wireless Ethernet connection and the
wireless access point's DHCP settings vary from connection to connection (as
one would expect). The problem I'm having is that when connected over the
VPN, the laptops still use the DNS server addresses defined by the wireless
connection (and this also seems to be the case if connected via a land
line). Even though the VPN server hands out own set of DNS addresses,
client connections don't ever seem to use them. This results in our client
machines not being able to access some resources because of DNS lookup
failures. Is there any way to force a machine to use the connection
settings handed to it by a VPN server instead of those provided through a
prior connection (regardless of whether the prior connection is wireless or
a physical land line)? Any and all assistance is appreciated.

Thanks.

 

[Wocka]

On W2K I use the following, should be the same in XP.

On the connector for the VPN dialler, right click / properties / networking
tab
Click on "Internet Protocol TCP/IP."
Select properties.
Select "Use the following DNS server Address's" radio button.

Type in your network DNS servers.

Even though RAS should issue the VPN client all the local IP / DNS settings
I have found that I need to use this option, especially when using the
"Logon using Dial up Networking" at the Crtl + Alt + Del screen