Pkg exim4 users - Dec 2007 - spam filter irritated by duplicate headers

I just encountered an error(?) with debian''s default spam acl:

   warn
     spam = Debian-exim:true
     message = X-Spam_score: $spam_score\n\
               X-Spam_score_int: $spam_score_int\n\
               X-Spam_bar: $spam_bar\n\
               X-Spam_report: $spam_report

This acl seems to check also my outgoing mail. So this message, which
I''m
sending now to the mailing list will be scanned on sending and once again on 
receiving back from the list.

This means, that there will be two sets of X-Spam_... headers which leads to 
the following error:

The userforwardspam router encountered the following error(s):

? malformed numerical string "1
2"

No valid addresses were generated.

The filter is
if "${if def:header_X-Spam_score_int:{true}}" is true then
    if $header_X-Spam_score_int is above 70 then
        pipe "/usr/lib/dovecot/deliver -m spam"
    endif
endif

The mail contains 
X-Spam_score_int: 1
X-Spam_score_int: 2
both added by my server.

Should I rather check for $spam_score_int instead of $header_X-Spam_score_int 
in my my userfilter?

There''s already an exim bug asking for the ability to remove headers at
acl
time:
http://bugs.exim.org/show_bug.cgi?id=501

Cheers,

Thomas Koch

Thomas Koch <thomas at koch.ro> wrote:
[...]
> Should I rather check for $spam_score_int instead of
$header_X-Spam_score_int
> in my my userfilter?
Yes, you should do that.
> There''s already an exim bug asking for the ability to remove
headers at acl
> time:
> http://bugs.exim.org/show_bug.cgi?id=501
You can use a system filter to do that alternatively.

# acl
   warn condition = ${if <{$message_size}{120k}{1}{0}}
        spam = nobody:true
        set acl_m0 = $spam_score ($spam_bar)
        set acl_m1 = $spam_report
[...]

# Exim filter
if first_delivery then
  headers remove X-Spam-Score:X-Spam-Report
  if $acl_m0 contains "("
  then
    headers add "X-Spam-Score: $acl_m0"
    headers add "X-Spam-Report: $acl_m1"
  endif
endif

cu andreas
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