[Exim] condition issues / amavis & mysql

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Greetings


I'm having some trouble with router conditions under exim4

I want to offer the amavis anti-virus service to all of my users hosted
on my mailserver, but I still want to be able to enabled/disable the
service on a per-user basis. So I tried with the following condition:

condition = "${if and { \
          {eq {$received_protocol}{scanned-ok} {0}{1}} \
          {eq {${lookup mysql{SELECT checkvirus FROM users WHERE
checkvirus='yes' AND username='$local_part' AND
domain='$domain'}}{1}{0}} \
          }{yes}{no}}"

But it doesn't work. Can please somebody help me out with this
condition. Amavis should only scan the mail if the user has
checkvirus='yes' and if the mail hasn't already been scanned. Or if at
least somebody could point me to a page with some documentation/examples
regarding conditions under exim4.



Thanks a lot

Yves
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