How to skip DNSBL checks for authenticated main in Exim4

Question

I have the following ACL with Exim4:

acl_check_rcpt:
    deny message  = DNSRBL Access denied - $sender_host_address \ 
                    listed by $dnslist_domain\n$dnslist_text 
         dnslists = zen.spamhaus.org : b.barracudacentral.org

This applies the DNSBL to all mail, but I'd like to add an exception to only check incoming mail (or to skip the checks for mail delivered via an SMTP-authenticated session).

Answer 1

It seems easiest to me to just juggle the order of the tests in acl_check_rcpt such that something like the following is above the DNSBL test you're having trouble with:

accept  authenticated = *

So, rather than adding an exception to the DNSBL check, you simply accept the mail before you ever get to the DNSBL check if the sender is authenticated.