[Exim] Alias file

Hello
I have an alias director set up to handle class lists where
authentication is necessary. The problem is
I have the $authenticated_id available on the first pass but on the
second it fails because $authenticated_id
is no longer set. Here is sample message that was put through by
omitting the $authenticated_id check in
the director.

                  Received:
                            from beta.cl.msu.edu (beta.cl.msu.edu
[35.8.3.52]) by pilot08.cl.msu.edu
                            (8.10.2/8.10.2) with ESMTP id f2UDvk538032
for <akb@???>; Fri,
                            30 Mar 2001 08:57:46 -0500
                  Received:
                            from pilot01.cl.msu.edu ([35.9.5.21]) by
beta.cl.msu.edu with esmtp
                            (Exim 3.20 #10) (TLSv1:DES-CBC3-SHA:168) id
14izSP-0003XJ-00
                            for ss01-fi-414-2@???; Fri, 30
Mar 2001 09:00:54 -0500
                  Received:
                            from denali.cl.msu.edu ([35.8.1.214]
helo=msu.edu) by
                            pilot01.cl.msu.edu with asmtp (Exim 3.22 #2)
(SSLv3:RC4-MD5:128)
 akb is $authenticated_id in line below
                            (authenticated as akb) id 14izPH-0003jg-00
for
                            ss01-fi-414-2@???; Fri, 30 Mar
2001 08:57:39 -0500
                    Sender:
                            tony@???
               Message-ID:
                            <3AC4915C.170711E3@???>
                      Date:
                            Fri, 30 Mar 2001 08:59:57 -0500
                      From:
                            tony <akb@???>
                  X-Mailer:
                            Mozilla 4.76 [en] (X11; U; FreeBSD
4.2-RELEASE i386)
        X-Accept-Language:
                            en
             MIME-Version:
                            1.0
                        To:
                            ss01-fi-414-2@???
                    Subject:
                            17
              Content-Type:
                            text/plain; charset=us-ascii
 Content-Transfer-Encoding:
                            7bit
                 X-Scanner:
                            exiscan *14izSP-0003XJ-00*BTkv0Q7lRIE*
                            http://duncanthrax.net/exiscan/

And this is the director

special_director:
condition = ${if match{$local_part}{....-.+-.+-.+}{true}{false}}
driver = aliasfile
search_type = mysql

query = Select student from clist left join author using (course) where
sem = '${quote_mysql:${extract{1}{-}{$local_part}}}' and clist.sub =
'${quote_mysql:${extract{2}{-}{$local_part}}}' and clist.course =
'${quote_mysql:${extract{3}{-}{$local_part}}}' and section =
'${quote_mysql:${extract{4}{-}{$local_part}}}' and name =
'$authenticated_id'


Thanks

AKB