dovecot - Jan 2012 - 2.0.17: Index lost -> SAVEDON lost as well?

Today I encoundered these errors:

Jan  9 08:30:06 mail dovecot: lmtp(31174, backup at backup.invalid): Error: Log
synchronization error at seq=858,offset=44672 for
/home/mailboxname/mdbox/storage/dovecot.map.index: Append with UID 282388, but
next_uid = 282389
Jan  9 08:30:06 mail dovecot: lmtp(31819, backup at backup.invalid): Error: Log
synchronization error at seq=858,offset=44672 for
/home/mailboxname/mdbox/storage/dovecot.map.index: Append with UID 282388, but
next_uid = 282389
Jan  9 08:30:06 mail dovecot: lmtp(32148, backup at backup.invalid): Error: Log
synchronization error at seq=858,offset=44672 for
/home/mailboxname/mdbox/storage/dovecot.map.index: Append with UID 282388, but
next_uid = 282389

After that, the SAVEDON date for all mails was reset to today:

mail:~# doveadm search -u backup at backup.invalid mailbox INBOX SAVEDON
2012-01-09 | wc -l
75650
mail:~# doveadm search -u backup at backup.invalid mailbox INBOX SAVEDON
2012-01-08 | wc -l
0
mail:~# doveadm search -u backup at backup.invalid mailbox INBOX SAVEDON
2012-01-07 | wc -l
0

Before, I was running this:
vorgestern=`date -d "-2 day" +"%Y-%m-%d"`
doveadm expunge -u backup at backup.invalid mailbox INBOX SAVEDBEFORE
$vorgestern
doveadm purge   -u backup at backup.invalid

Is there a way of restoring the SAVEDON info?

-- 
Ralf Hildebrandt
  Gesch?ftsbereich IT | Abteilung Netzwerk
  Charit? - Universit?tsmedizin Berlin
  Campus Benjamin Franklin
  Hindenburgdamm 30 | D-12203 Berlin
  Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
  ralf.hildebrandt at charite.de | http://www.charite.de

On 9.1.2012, at 9.40, Ralf Hildebrandt wrote:
> Today I encoundered these errors:
> 
> Jan  9 08:30:06 mail dovecot: lmtp(31174, backup at backup.invalid): Error:
Log synchronization error at seq=858,offset=44672 for
> /home/mailboxname/mdbox/storage/dovecot.map.index: Append with UID 282388,
but next_uid = 282389
Any idea why this happened?
> After that, the SAVEDON date for all mails was reset to today:
Yeah. The "save date" is stored only in index. And index rebuild drops
all those fields. I guess this could/should be fixed in index rebuild.
> Is there a way of restoring the SAVEDON info?
Not currently without extra code (and even then you could only restore it to
e.g. its received date).

On 9.1.2012, at 16.57, Timo Sirainen wrote:
>> After that, the SAVEDON date for all mails was reset to today:
> 
> Yeah. The "save date" is stored only in index. And index rebuild
drops all those fields. I guess this could/should be fixed in index rebuild.
Fixed: http://hg.dovecot.org/dovecot-2.0/rev/c30ea8aec902