[Mimedefang] md_check_against_smtp_server() REJECTing everyone

[Delahunty, Mark]

Apologies if this has been covered already.

I can't  get md_check_against_smtp_server to return "OK" for a valid user

Here's the relevant bit from mimedefang-filter

sub filter_recipient {
    my ($recipient, $sender, $ip, $hostname, $first, $helo) = @_;
    my $thishost = "mail7.MYDOMAIN.EDU" ;  ## This host (or anything that
resolves?)
    if ( $recipient =~ /\@student\.MYDOMAIN\.EDU>?$/i )   {
       logv("Checking for user $recipient on SMTP server student
RECIP:$recipient  FIRST:$first SENDER:$sender  RELAY:$ip/$hostname
HELO:$helo") ;
       my @rec_chk = md_check_against_smtp_server($sender, $recip,
$thishost, "student.MYDOMAIN.EDU") ;
       open (rec_log, ">>/tmp/rec_log");
       print rec_log join(":", at _), "\n", join(":", @rec_chk), "\n\n";
       close (rec_log);
    } else {
      logv("Not Checking for user $recipient on SMTP server RECIP:$recipient
FIRST:$first SENDER:$sender  RELAY:$ip/$hostname  HELO:$helo") ;
    }
 
###########################################################################


Every user, whether valid or nonexistent gets "User address
required:553:5.0.0"
Here's an example entry from /tmp/rec_log

<l.realuser at student.MYDOMAIN.EDU>:<someuser75 at hotmail.com>:64.4.49.20:bay14-
f20.bay14.hotmail.com:<l.realuser at student.MYDOMAIN.EDU>:hotmai
l.com:esmtp:student.MYDOMAIN.EDU.:l.realuser at student.MYDOMAIN.EDU
REJECT:<>... User address required:553:5.0.0

But L.REALUSER gets a "Recipient ok" in SMTP to the mailbox server:

[root at mail0 root]# telnet student 25
Trying 143.239.1.13...
Connected to student.
Escape character is '^]'.
220 student.ucc.ie ESMTP Sendmail 8.12.8/8.12.8; Thu, 4 Mar 2004 22:53:35
GMT
helo mail7
250 student.ucc.ie Hello mail0.ucc.ie [143.239.1.30], pleased to meet you
mail from: somebody at MYDOMAIN.EDU
250 2.1.0 somebody at MYDOMAIN.EDU... Sender ok
rcpt to: l.realuser at student.MYDOMAIN.EDU
250 2.1.5 l.realuser at student.MYDOMAIN.EDU... Recipient ok
rcpt to: l.realuser
250 2.1.5 l.realuser at student.MYDOMAIN.EDU... Recipient ok
quit
221 2.0.0 student.MYDOMAIN.EDU closing connection
Connection closed by foreign host.

Any ideas?
Is there a way to debug md_check_against_smtp_server?

TIA

Mark Delahunty
UCC Computer Centre
Cork
Ireland