Internet Sharing Dialin Client to XP Ser

I have a major problem trying to link through a PC [setup as a Server]running XP and
connected by broadband to the internet. The link is a external PC [at another address] that dials in via the Hub and can connect to the network but gets an error message that the DNS server cannot be located when trying to connect to the network.

Do you know of a published process that details the appropriate settings for both these PCs to allow this access ? I suspect that given the
number of settings available and their combinations I believe I have
covered them all and it looks like XP Pro just does not support this.