Hypermail can deal with attachments enclosed in MIME messages.
For more information on MIME 

   + RFC 2045, which specifies the various headers used to describe
     the structure of MIME messages.

   + RFC 2046, which defines the general structure of the MIME media
     typing system and defines an initial set of media types,

   + RFC 2047 which describes the  Message Header Extensions for 
     Non-ASCII Text

   + RFC 2048, which specifies various IANA registration procedures
     for MIME-related facilities, and

   + RFC 2049, which describes MIME conformance criteria and
     provides some illustrative examples of MIME message formats,
     acknowledgements, and the bibliography.

   + RFC 2383, which describes Communicating Presentation Information 
     in Internet Messages: The Content-Disposition Header Field.

Saving Attachments:
-------------------
  
When hypermail encounters an attachment it saves the attachment to disk as a
separate file. The basename of the filepath specified in the message is used
as the rightmost part of the filename used to store the attachment file,

    <a href="att-<msgnum>/<num>-budget.doc">budget.doc</a>

<msgnum> - The number used for the message in which this attachment was found.
<num>    - The MIME part number, simply numbered from top-to-bottom in the
           mail this attachment was found.

In the event that there is no file name specified in the message then
a random name is generated instead. 
 
Hypermail prints a comment in the message HTML file to indicate the message 
has an attachment and what the name of the attachment file is.

           <!-- attachment="filepath1" -->
           <!-- attachment="filepath2" -->
           ...
           <!-- attachment="filepathN" -->

Besides making it much easier for removal or converter processes, standard
incremental mailbox updates will be able to recognize that there are
attachments and use the existing filenames or remove them prior to generating
new ones.

Attachment File Modes:
----------------------

      For security reasons, all binary attachments written to disk get the
      same file permissions as the ordinary messages. They should never be to
      be executable, to any user.

Controlling archiving of attachments
-------------------------------------

       The user can control the use of attachments by:

       1. Indicating which mime types should not be stored at all.  
          (i.e. vcard attachments) (see ignore_types)

       2. Specifying a list with 'preferred' content-types when 
          receiving/decoding mixed/alternative attachments
          (see prefered_types)

       3. Indicating which content-types of images that is preferred 
          to get in-lined - <img> instead of <a href>.
          (see inline_types)

       4. Use the 'attachmentlink' config file keyword to control how to
          "display" the attachment. You can for example use this to always
          display a warning page before the actual attachment is displayed or
          run by a client.

Config file additions: 
----------------------

   # For each type to be ignored, put an ignore record for that
   # type. It is added to the list of ignored types when the config
   # file is read.
   #
   ignore_types = text/x-vcard
   ignore_types = application/x-msdownload

   #
   # ordered list, Do the first and if that is not present, 
   # do the next and if that is not present ...
   #
   prefered_types = text/plain text/html ...

   #
   # Determine which image mime types should be inlined for
   # display in the message. <IMG SRC=..> instead of <A HREF=...>
   #
   inline_types = image/gif image/jpeg ...

   #
   # Format of the attachment links.
   # %p for the full path to the attachment
   # %f for the file name part only
   # %d for the directory name only
   # %n for the message number
   # %c for the content type string
   #
   attachmentlink = %p

The readconfigs function is now able to look for more than one entry of
certain types of variables. This can be on one line or on multiple lines. This
type of parsing is only supported for

	ignore_types
	inline_types
	prefered_types