[Dovecot] convert plugin: endless conversion and duplicate messages

[Andrew Ziem]

Hi,

When an mbox has a filename with a period, the Dovecot 1.0.1 convert 
plugin will endlessly convert the same mbox causing duplicate messages.  
To reproduce, create try converting two mboxes: one with a valid name 
and another with an invalid name.  Then, repeat the login procedure a 
few times.

Dovecot should do something more graceful such as replacing periods with 
another character.

Here's /var/log/mail/errors
Jul  2 08:29:44 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 08:39:46 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 08:48:54 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 08:48:58 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 08:49:39 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 08:59:40 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 09:09:40 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name
Jul  2 09:20:23 aslan dovecot: IMAP(crystalp): Mailbox conversion: 
Couldn't create mailbox Print Shop Misc.: Invalid mailbox name

I didn't test other non-{alphanumeric,whitespace} characters.

Other than this and my previous e-mails, our conversion from UW-IMAP 
mboxes went nicely.  I notice the performance difference, and our users 
will be happy to finally have proper subfolders.


Andrew