dovecot - Oct 2014 - courier-imap to dovecot

Hello! I am here since my boxes (40000 emails in folders) are not
usable with roundcube and courier-imap. Server is core 2 quad, 4GB RAM
and 1TB HD. Which are steps for migration for about 40 Maildir boxes
to dovecot?

-- 
Saludos!!

Luciano Andino
GNU/Linux user #185103
Santa Fe - Argentina
-----------------------------------------------