Using dovecot with existing mbox hieararchy - possible?

[Chris Green]

I currently use mutt to read my E-Mail on a machine which runs a
postfix server to receive mail by SMTP.  Mail is actually delivered to
the final mbox mailboxes by a custom filtering script writtin in
Python. 

Will dovecot happily serve mail from the existing hierarchy (obviously
if I configure it right) so that I can connect using IMAP to my server
machine to read mail?

The mbox files are all under ~/Mail with several levels of directories
in some trees.

Does dovecot need any sort of notification from postfix (or my Python
script) to indicate that new mail has been delivered or does it just
re-scan the mbox files at intervals to see changes?

-- 
Chris Green