[Exim] Five domains in the same machine

How can I do for make the same machine manage 5 domains with separate
aliases file and users.
begin: vcard

fn:             Gustavo Palacios
n:              Palacios;Gustavo
org:            PETROECUADOR. Sistemas
adr:            Alpallana E8-86 y 6 de Diciembre;;;Quito;Pihcincha;;Ecuador
email;internet: gpalacios@???
title:          Analista de Sistemas 2
tel;work:       593-2-562-502
x-mozilla-cpt:  ;0
x-mozilla-html: FALSE
version:        2.1
end:            vcard