[exim] more SA problems

Hello People!

Well, i've beem bugging you all with some emails about my SpamAssassin
problems. I've beem doing some tests:
First I added the following line in the session ACL at the config file:

    warn message = X-Spam-Score $spam_score ($spam_bar)
              spam = nobody:true

restarted the service (# invoke-rc.d exim4 restart) and sent me an 
email. I didnt sent an email throught the method
    # echo "test" | mail -s "testing" USER
I just wrote an mail to myself with my Thunderbird. And no header was 
added to my emails :(

Then i removed one line and left it like this:

        warn message = X-Spam-Score $spam_score ($spam_bar)

Did the same again (restarted and sent me an email throught Thunderbird)
and a little header was added (Finally!)

        X-Spam-Score ()

And only this

Well, I understand that spamd is not running, but it is!... I restarted
SpamAssassin and did the same and nothing!... What am i doing wrong?!
Any light in the end of the tunnel?!


Thanks for all!