[Dovecot] Corrupted index cache files

[Mike Abbott]

> How soon? With what kind of imaptest parameters? I can't reproduce  
> this on my Macbook (OS X 10.5.4, HFS+).

I ran imaptest for just a few minutes and saw all these errors in that  
time.  Default imaptest parameters except for user/host names etc.

>> Error: UIVALIDITY changed: %d -> %d
>
> Did you test with a single user or multiple users? imaptest's  
> support for testing multiple users is currently a bit broken, but  
> this shouldn't happen with a single user..

This error happens with clients=1, clients=10 and clients=100.

>> Error: user%d[%d]: <...>: Header CC changed
>> Error: user%d[%d]: <...>: Header DELIVERED-TO changed
>> Error: user%d[%d]: <...>: Header FROM changed
>
> These shouldn't be happening as long as you use a test mbox file  
> that has unique Message-ID headers. Were you using the recommended  
> dovecot-crlf as the input?

I passed in your dovecot-crlf file to imaptest, but the message store  
was cloned from elsewhere first.  So you're saying that dovecot only  
works with special hand-crafted input, and not with real-world mail?   
Hmmm.... :) :)

Actually I do see plenty of duplicate Message-ID headers in the mail  
store (not from your input file).  I'll investigate that further.   
Thanks for the tip.