That was the problem, thanks!
> On Fri, Apr 07, 2006, christian meutes wrote:
>> i have a problem with my exim/spamassassin setup. It seems that exim isnt
>> defering mails when there arises a problem with the spamc<->spamd pipe
>> delivery.
> [...]
>> I believe that exim doesnt defer the mails instead it forward them to the
>> next router.
>
> well, it's not exim, actually. spamc(1) states:
>
> -x Disables the 'safe fallback' error-recovery method, which passes
> through the unaltered message if an error occurs. Instead, exit
> with an error code, and let the MTA queue up the mails for a retry
> later. See also "EXIT CODES".
>
> -- sh
>