[Dovecot] Modifying the underlying maildir externally (webmail, replication)

[Attila Nagy]

Hello,

I have a setup where there are multiple maildir users, one of them being 
the pop/imap server itself, the others are for example a maildir capable 
webmail and message replication.

I would like to evaluate Dovecot, but I wonder how would its binary 
indexes and logs fit into this picture.

After running through http://wiki.dovecot.org/IndexFiles I'm not sure 
how well would Dovecot work with other programs modifying the maildirs 
(adding, deleting, moving messages, folders etc).
The "Main index" section says "The index file is synchronized against 
mailbox only if the syncing information changes.", where syncing 
information consists or cur and new directories' timestamps.
Does that mean I am safe there?

The cache file is hopefully just a cache, so it won't contain 
information from messages which are inserted or moved by an external 
program, and I assume Dovecot fetches the message lists and other 
information from the main index, which seems to be OK.

The transaction log is for the main index, so if the latter is OK, the 
former should be OK too.

http://wiki.dovecot.org/MailboxFormat/Maildir talks about MUAs and there 
nothing scary can be found, except for some temporary conditions, where 
the changes won't propagate to Dovecot in real time, but it's OK.

Are the above right, and can Dovecot use its indexes and caches safely 
with others using the same maildirs?

Thanks,