[exim] Exim and virtual users

Hi

I have set up a new exim web server and it works fine with dovecot, pg-
sql and exim-4.44 for defined local users.

I want to add some virtual users, via postgres, and it appears to work
apart from the Exim sender/recipient tests. I keep getting

Unknown user

errors for these accounts.

Is there a simple, recommended was for allowing virtyal users, defined
in a Postgres table to send and recieve mail?

If I create empty user accounts, then mail is processed.

Thans

Simon
--
Simon Windsor
Email: simon.windsor@???
Tel: 01454 617689
Mob: 07960 321599