[Exim] [soleil]Restricting Access on a transport/director

Hi,

I run a Fax Server incorporating HylaFAX and Exim and the process involves a single transport and
director. I would like to limit access to this service via any of those two, if that could be possible.
I could have authentication, say, against a username:passwd combination in a file in a user's $HOME.
I don't intend to have AUTH in the whole server, only for the fax service. Is there a HOWTO for this
somewhere I can access?? Restriction can also be achieved via HylaFAX itself but someone can fake an
e-mail address and circumvent that, so I don't really like it.

Thanking you all.

-Wash

--
Odhiambo Washington
Wananchi Online Ltd.,
wash@??? 1st Flr Loita Hse.
Tel: 254 2 313985 Loita Street.,
Fax: 254 2 313922 PO Box 10286,00100-NAIROBI,KE.

Question with boldness even the existence of a God; because, if there be one,
he must more approve of the homage of reason, than that of blind-folded fear.
-Thomas Jefferson