Log Message:
Upgrade to version 1.76.  Notable changes:

-   The most common/important file formats are recognized based on file
    contents, not just file name and MIME-type.  Detects WMF files, to
    allow reliable blacklisting.  Detects when people try to disguise
    non-JPEG/GIF/PNG content as such files and defangs such attachments.

-   Bug fixed, where disinfection wouldn't result in the modification
    count of a message being incremented.  Some 3rd party systems rely
    on the modification count to determine whether to use the output or
    not.  This is a critical fix for such systems.

-   Improved handling of Yahoo DomainKeys.

-   Fixed crash when multiple Content-Transfer-Encoding headers were
    present in the same message part.

-   Added mailblogger.pl, to the distribution.  This program has
    nothing to do with security, but uses the MIMEStream parser to
    extract images from e-mail and can subsequently generate thumbnails
    and re-post both text and images to a web-site, to implement
    email-to-www gateway functionality.  (E.g. mobile blogging.)