[exim] Blacklists

Hi,

I have the following in my configure file to block mail on a certain
blacklist. However, I want to allow the IP if the user is authenticated.
However, it doesnt seem to be working...

Is the syntax incorrect? should it be authenticated = !* ?

   deny    message       = Access denied - $sender_host_address listed  
by $dnslist_domain\n$dnslist_text
           !authenticated = *
           hosts         = !+relay_from_hosts
           dnslists      = dnsbl.sorbs.net

Jonathan