[Exim] Funny behaviour with system_filter.exim

Hi,

Allow me to ask why this is happening:

I am using the Exim system_filter.

While running with Exim-3.22 it used to give a message like (1) below when
it catches one of those files.
Now with Exim-3.31 (nothing changed in the configure file) it gives a
message like (2) below. Exim on FreeBSD compiled from tarball.

Thanks.

1.
<snip>

From: Mail Delivery System <Mailer-Daemon@???>
Reply-To: admin@???
To: root@???
Date: Thu, 05 Jul 2001 15:59:11 +0300
Subject: Mail delivery failed: returning message to sender

This message was created automatically by mail delivery software (Exim).

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  rajinder@???
    This message has been DELIBERATELY rejected because it has
        a potentially executable attachment "UNREGASF.EXE"
        This form of attachment has been used by
        recent viruses or other malware.
        If you _REALLY_ meant to send this file then please
        package it up as a ZIP file and resend it.
        IF YOU DON'T KNOW WHY YOU'RE RECEIVING THIS, PLEASE RUN
        YOUR ANTI-VIRUS SOFTWARE TO CHECK FOR ANY POSSIBLE INFECTION.
</snip>

2.

<snip>
From: Mail Delivery System <Mailer-Daemon@???>
Reply-To: admin@???
To: Mailer-Daemon@???
Date: Tue, 17 Jul 2001 16:06:47 +0300
Subject: Mail delivery failed: returning message to sender

This message was created automatically by mail delivery software (Exim).

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  info@???
    This message has been DELIBERATELY rejected because it has
    \ta potentially executable attachment "ICWIN95.EXE"
    \tThis form of attachment has been used by
    \trecent viruses or other malware.
    \tIf you _REALLY_ meant to send this file then please
    \tpackage it up as a ZIP file and resend it.
    \t
    \tIF YOU DON'T KNOW WHY YOU'RE RECEIVING THIS, PLEASE RUN
    \tYOUR ANTI-VIRUS SOFTWARE TO CHECK FOR ANY POSSIBLE INFECTION.
</snip>

-Wash

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