Hi Eugene,
But really, all this leads is that admin has to detect the dovecot
termination and simply go and restart it manually -- after some bad
thoughts. During normal operation, on 99% of the hosts, the clock should never need to leap backwards. So if that ever happens, it seems fine for dovecot to stop and require admin intervention. This is perhaps not ideal, but it sure beats dovecot making mails disappear or doing other funky and undefined stuff.
If you happen to have a system on which this is in fact common, then you should find some way to deal with this yourself, preferably by not making the time leap backwards :-)
I'm not saying there shouldn't be any improvements to handle this in dovecot, but I think it's not so trivial to handle this properly, without risking data loss (as Timo pointed out, immediately restarting is not really helping, since you'll still be running in the past. AFAIU, dovecot should at least wait with restarting until the backwards leap time has passed again, which seems rather non-trivial to implement).
Gr.
Matthijs