Exim still accepting emails to nonexistent users

[Marti Markov]

After adding the configuration bit:

deny
        message = invalid recipient
        domains = +local_domains
        !verify = recipient/callout=no_cache

from: http://wiki2.dovecot.org/LMTP/Exim <http://wiki2.dovecot.org/LMTP/Exim> 
running update-exim4.conf and service exim4 restart

the server is still accepting emails to recipients that do not exist in dovecot.

Any ideas?