[exim] check the DNS check

Hi all,

In my Exim (the one packaged in Debian Squeeze):

CHECK_RCPT_IP_DNSBLS = sbl-xbl.spamhaus.org : bl.spamcop.net

I ran "update-exim4.conf" then restarted Exim.

How to check then that the lookup is effective?

Logs aren't telling anything...
With tcpdump? DNS requests are much.

--
RMA.