[Mimedefang] REJECT in filter_relay not returning proper code?

[Jim McCullars]

Hi, I have this as part of my filter_relay:

sub filter_relay {
  my($ip, $name) = @_;
  return(1) if ($ip eq "127.0.0.1");   # no further checking if localhost
  if($name =~ /dsl.+(?:prodigy|prod-infinitum)\.(?:com|net)\.mx/i ||
     $name =~ /dsl.+(?:sw|pac)bell\.net/i ||
     $name =~ /pool.+verizon\.net/i ||
     $name =~ /modemcable.+videotron\.ca/i ||
     $name =~ /dsl.+ameritech\.net/i) {
    return('REJECT', "Mail from client IP addresses not accepted.");
  }

Someone from an ADSL swbell address is trying to send me email and it is
getting rejected by filter_relay.  The log message on my end is this:

Mar 17 10:45:52 smtp-in1 mimedefang.pl[1148]: [ID 702911 mail.debug]
filter_relay rejected host 64.216.205.121
(adsl-64-216-205-121.dsl.stlsmo.swbell.net)
Mar 17 10:45:52 smtp-in1 sendmail[2680]: [ID 801593 mail.info]
j2HGjqK7002680: Milter: connect:
host=adsl-64-216-205-121.dsl.stlsmo.swbell.net, addr=64.216.205.121,
rejecting commands

but the sender, rather than seeing the more descriptive message about what
the problem is, sees only this:

554 smtp-in1.uah.edu ESMTP not accepting messages

  Is this a problem with MD, my code, sendmail, or something else?
Thanks...

Jim McCullars
University of Alabama in Huntsville