[exim] DATA ACL and conditions

Hello,

I can't get the condition option to work with DATA ACL. I have the following :

  warn message          = X-Spam-Report: $spam_report
       spam             = joe:true
       condition        = false

and still, Spamassassin gets called everytime a message arrives.

Reading the manual, it seems to me that the condition option only applies AFTER Spamassassin has been called. Am I right ?

Actually, I'd like the antispam filter to be called only if the use wishes to (say, if a file <user>.spam exists).

Thanks in advance.

Christian