F-SECURE INTERNET GATEKEEPER WINDOWS 2000-2003 SERVER 6.61 Administrator's Manual page 193

Action on mails with
long lines
Examples of Malformed Messages
Malformed mail headers can include, for example: Multiple Content-Type,
Content-Disposition and/or Content-Transfer Encoding headers, multiple
"name" parameters in Content-Type headers, or multiple "filename"
parameters in Content-Disposition headers.
In the example below, there are multiple "Content-Transfer-Encoding"
headers with different values (base64 and the other quoted-printable):
This is a multi-part message in MIME format.
--SHNJUU7CST-=-1AEAS11JMG-CUT-HERE-YRVJUFHDDE-=-ASN1DH889T
Content-Type: application/octet-stream
Content-Transfer-Encoding: base64
Content-Transfer-Encoding: quoted-printable
Content-Disposition: attachment;
filename="ghost.exe"
Administering F-Secure Anti-Virus for Internet Mail
Select the action to take if an e-mail message
contains lines exceeding the maximum length of
995 characters (not including <CRLF>).
Reject - The e-mail is rejected.
Wrap - The product accepts the e-mail message
and splits long lines (as soon as they are
encountered during receiving) into multiple lines,
each of them shorter or equal to 995 characters.
When wrapping long lines, lines over 995
characters are split with a carriage return, line
feed and tab. This means that the first line starts
from the beginning, but each additional wrapped
line is indented with a tab. This is done to avoid
breaking the MIME headers.
Accept - The e-mail is accepted with the long
lines unmodified. This may cause problems with
downstream mail servers.
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