[exim] Is Exim removing X-Spam-Flag headers ?

Hello List,

I'm pretty new to Exim and can't solve following problem, after
desperately googling the archives.

I'm using Exim 4.54 and Spamassassin 3.1.1.
Exim works great without Spamassassin.
Spamassassin (from now on called SA) works great alone aswell.
But if SA is called via Exim some of the X-Spam-* Headers are removed.
Especially X-Spam-Flag and X-Spam-Status, which is needed from my
Mailclient to identify Spam. Trying to add that as $spam_status
results in "Unknown Variable".
Declaring "status _YESNO_" in SA's local.cf doesn't help either nor
setting "report 0".
This is somehow only the first part.
Emails contaning only "test" for testing purposes, are being detected
as Spam. Testing it on the commandline shows no spam.
(spamassassin < testmail.txt) and of course include all the X-Spam
Headers I need.
The problem occurs, after Exim has checked the mail with SA.

Am I missing something ?

My config looks like this:
-----
acl_check_data:

     warn    spam      = nobody
           message   = X-Spam-Score: $spam_score\n\
                             X-Spam-Flag: $spam_report\n

                      #X-Spam_score_int: $spam_score_int\n\
                      #X-Spam_bar: $spam_bar\n
                      #X-Spam_report: $spam_report

# Accept the message.

accept

------

spamcheck_router:
no_verify
check_local_user
condition = "${if and { {!def:h_X-Spam-Flag:} {!eq
{$received_protocol}{spam-scanned}}} {1}{0}}"
driver = accept
transport = spamcheck
-----

spamcheck:
    driver = pipe
   # batch_max = 100
    command = /usr/sbin/exim -oMr spam-scanned -bS
    use_bsmtp = true
    transport_filter = /usr/bin/spamc
    home_directory = "/tmp"
    current_directory = "/tmp"
    # must use a privileged user to set $received_protocol on the way back in!
    user = mail
    group = mail
    log_output = true
    return_fail_output = true
    return_path_add = false
    message_prefix =
    message_suffix =

----

Best regard, Zafer.