[Exim] Conditionally director

Hi,
using amavis, I would like to use a per-user scanning condition. So, I have
users that have to be (or have to be not, as you prefer) scanned in a
file...how can I use the director I created for amavis only if the user is
listed (or not) in the file ? Here is what I have now as condition:

  condition = "${if or {{eq {$received_protocol}{scanned-ok}}} \
    {0}{1}}"

I tries to change it, i.e. in:
  condition = "${if or {{eq {$received_protocol}{scanned-ok}}} \
    ${lookup{$user} lsearch {/etc/exim/antivirus-mail} {0} {1}}" \
    {0}{1}}"

and other things like that...maybe (of course) I have not fully understood,
but howcan I do this work ?

--

Bye
                            +--------+ Maybe you are searching for freedom
                            | Enrico |    Maybe you can't find it anywhere
                            +--------+          I found it in linux.......

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