[exim] Deny mails to specific recipients

Hello!

I want to reject all mails which are addressed to specific addresses which
I specify in a file. I did this by adding the following to the config file
in the acl_check_rcpt: section:

  deny    message = No such user
          recipients = lsearch;/etc/aliases-reject

As I am rather a newbie I just want to be sure if this is a right way to
do it, or if I made a catastrophal error ;-)

Thank you,
Burt