I'm still seeing some of these in the CVS version as of Oct. 6:

dovecot: Oct 07 11:09:42 Error: child 2410 (imap) killed with signal 14

It's happening quite a bit less since this fix:

2005-09-30 18:25 Timo Sirainen tss@iki.fi

     * src/lib-index/mail-index-lock.c: Don't leak alarm() with
       in-memory indexes

Todd