I had added a a couple of extra RBL lists to my configuration so I
now have a total of 3 RBLs in use. This has helped massively to cut
down on spam but I have found a couple of legitimate mails being
blocked. I do not want to stop using the list at dsbl.org but would like
to make a couple of email addresses as exceptions. I thought the
best place to do this would be in the recipients_reject_except. I have
added the sender domain address but I notice that they are still being
rejected.