[exim] Multiple users for SMTP Authentication

Hi,
We have a requirement to handle some mail for 2 external clients. They need
to send as well as receive email.

Up until now, we have had a common authenticator for our own staff so that
they can send email from outside the office.

ie.

fixed_cram:
driver = cram_md5
public_name = CRAM-MD5
server_secret = ${if eq{$1}{username}{password}fail}
server_set_id = $1

fixed_plain:
driver = plaintext
public_name = PLAIN
server_prompts = :
server_condition = ${if and
{{eq{$2}{username}}{eq{$3}{password}}}{yes}{no}}
server_set_id = $2

This has worked perfectly fine so far, but what we now need are separate
common authenticators for each of the clients we will be handling mail for,
without having to add each user individually to a password file and checking
against it.

What is the best way to alter the above authenticators for us to be able to
do this ?

My thoughts we to do this:

fixed_cram:
driver = cram_md5
public_name = CRAM-MD5
server_secret = ${if eq{$1}{username1}{password1}fail} OR ${if
eq{$1}{username2}{password2}fail}
server_set_id = $1

fixed_plain:
driver = plaintext
public_name = PLAIN
server_prompts = :
server_condition = ${if and
{{eq{$2}{username1}}{eq{$3}{password1}}}{yes}{no}} OR ${if and
{{eq{$2}{username2}}{eq{$3}{password2}}}{yes}{no}}
server_set_id = $2

But I'm not sure of the correct syntax for the server_secret and
server_condition lines.

Any help grately appreciated.

Michael Slater-Jones
Systems and Network Administrator
Fast Web Media Ltd