[Dovecot] sorting question

[Greg Trounson]

Johannes Berg wrote:
> Hi,
> 
> If I understand the thread sorting algorithm correctly (from
> draft-ietf-imapext-sort-17.txt and the code), it will sort like this
> (where I use numbers instead of dates with higher numbers being newer
> mails)
> 
> 4
>   10
> 3
>   11
> 2
>   12
> 1
>   13
> 
> etc into all the lower levels. Thunderbird will actually sort this like
> this:
> 
> 1
>   13
> 2
>   12
> 3
>   11
> 4
>   10
> 
...

You're lucky.

I've just installed Dovecot on a Debian Sarge machine here and am seeing 
some very strange thread sorting.

In Thunderbird on both Fedora and Debian clients, my threads served up 
by Dovecot look like this:

|-11
| `-12
|-2
|-3
|-4
| `-5
|   `-6
|     `-7
|       `-8
|-1
`-9
   `-10

Where the exact same threads served by Sendmail/imap look like this:

|-1
|-2
|-3
|-4
| `-5
|   `-6
|     `-7
|       `-8
|-9
| `-10
|-11
| `-12

Squirrelmail shows the threads correctly in both cases too, so I suspect 
there might be something funny going on with how Thunderbird handles 
Maildir threads.  I notice that Dovecot doesn't support the 
THREAD=ORDEREDSUBJECT capability, might that have something to do with it?

thanks,
Greg