Version:            (using KDE KDE 3.1KDE 1.2)
Installed from:    Unspecified LinuxUnspecified Linux
OS:          Linux

I have pasted here part of the Courier-IMAP 2.1.2 README file:

==BEGIN-OF-QUOTING==
SMAP

   Starting  with  Courier-IMAP  2.0, the server supports an experimental
   mail access protocol, dubbed "Simple Mail Access Protocol". SMAP is an
   experiment to provide enhanced mail processing beyond what's currently
   possible  with  IMAP.  SMAP's  purpose  is  to  prototype  and develop
   advanced  mail  access  functionality  that's  not possible with IMAP.
   Specifically:
     * SMAP  requires  approximately  25%  less  bandwidth  than  IMAP to
       download  large MIME attachments through low-bandwidth links. SMAP
       servers  unwrap  base64-encoded MIME attachments and send the raw,
       binary  content to the client, eliminating the 25% base64 penalty.
       A  similar  optimization  is  also  defined  by an unofficial IMAP
       extension,  but  it  is  also a fairly new extension, and does not
       have wide client/server support.
     * SMAP  allows  a  single  transaction  to save a new message in the
       "Sent"  folder,  and  mail  it  to its designated recipients. IMAP
       clients  need  to  transmit the message a second time, using SMTP,
       requiring  twice as much bandwidth and time as SMAP to do the same
       thing.
     * SMAP folder names use the full UTF-8 character set; unlike IMAP no
       restrictions  are  placed  on  which characters may be included in
       folder names.
     * SMAP  implements  both  the "mark/expunge" paradigm as IMAP, and a
       simpler "delete" process.
     * An  SMAP  client  does  not  need  to download the entire index of
       folder's  contents  when  reopening a previously seen folder. When
       reopening  a  folder,  the  client receives a much shorter list of
       changes  to  the  folder's contents since the last time the client
       had  the  folder  opened.  This  is  done by the client and server
       saving  an  index of folder's contents. After reopening the folder
       the  server only needs to send a list of changes between the saved
       folder index, and the current folder index.
     * Additional  internationalization  features  are  included  in  the
       design (but not yet used by the Courier implementation

   SMAP  is disabled by default. Uncomment the SMAP_CAPABILITY setting in
   the  imapd  configuration  file in order to enable SMAP. The Cone mail
   client supports SMAP.
==END-OF-QUOTING==

So. Let KMail support SMAP? And don't tell me the word "experimental" scares you :)) . Without wide email-client support the SMAP will never goes out of the "experimental" stage.

Thank you for the great work.