KMail folder not appearing

[Timothy Murphy]

I'm running KMail on my Fedora-17/KDE laptop,
collecting email from an dovecot/IMAP server
on a remote CentOS-6.3 machine that I control.

I created a new KMail folder "MathProblems"
by going to File=>New=>Add Folder on my laptop,
and I verified that this created a folder ~/Mathdir/.MathProblems
on the dovecot server (which stores email in ~/Mathdir),
with the usual cur, new, tmp sub-folders.
However, the files dovecot.index, dovecot.index.cache, etc,
do not appear in the .MathProblems folder
as they do in other similar folders,
and the folder does not appear in KMail on my laptop.

Is this a KMail or Dovecot bug?
And is there any way of creating the missing files?

Any advice or suggestions gratefully received.