Special answer for a request from a special network

[Laurent Jouannic]

Hi to the ML.

Well, here is the following situation:

I got some customers who are link to my private network by a 64K/Serial
link.
And I would like to setup the DNS to give a more apropriate answer for a
mail server if the request is from
the custumers behind the SL.

So, is it possible to specify a answer, if the request if from a special
adresse/network for a general name.

Thanks,

Regards.

Laurent Jouannic