[Dovecot] Support for Kmail maildir format

[Graham Cobb]

Has anyone looked into providing support in dovecot for Kmail folders?  I 
would like to make my Kmail folders (on my main desktop system) available to 
my other systems (including over a VPN when I am travelling).  Kmail is my 
main mail program and I have a lot of mail in a lot of folders, so I don't 
want to set up a separate IMAP service and move all the mail and folders.

Kmail's use of maildir seems to folow the basic maildir approach except that 
sub-folders are handled differently.

If you create a folder (say it is called ABC) in Kmail and start putting mail 
in it, Kmail creates a directory on the disk called ABC (not .ABC) and 
creates the cur, new and tmp folders within it to contain the email.

If you then create a subfolder of ABC (say it is called DEF, contained within 
the ABC folder), Kmail creates a directory on the disk called .ABC.directory 
and creates the DEF directory within that.

In other words, maildir directories are given the same name as the mail folder 
(with no leading dot) but sub-folders are contained in disk directories 
called .<folder-name>.directory.

I have taken a quick look at the dovecot code and am fairly sure this could be 
handled by a variant on the existing maildir code (e.g. by changes to 
maildir_fill_readdir and other routines).  Has anyone tried this?

Graham