[Dovecot] How Dovecot handles email changed by file operations

Hi,

We have been using Courier-imap for a few years. I am always in the process of reviewing competing software, and hence my interest in Dovecot.

Question: If email files are moved between IMAP folders (on the same IMAP server or a different one) or deleted using shell scripts, how does this impact Dovecot's indexes or its method of keeping track of the email? How likely is index or file corruption or race condition? An example, is the centralized removal of mail in all users' Junk folder older than 30 days.

We use Maildir format and Dovecot 1.0-RC7 with Mysql. We have about 150 users.

Thanks. Craig