i've had a qmail mail server running for some time now with no real
problems. this morning, one of the partitions in a mirror failed to
resync after a hard reset. the machine came back up fine on one of the
mirrors, and i went happily on my way. the filesystem with the failed
mirror was mounted on /var.

after the machine came back, any local delivery attempt gives the
error "deferral: Aack,_child_crashed._(#4.3.0)" i've tried completely
reinstalling qmail and copying the control files with no luck. i've
also tried installing qmail in /var/qmail and a seperate filesystem
(same device). i also get the same error (in the log) when sending
mail with qmail-inject, but one time i was able to send to a local
vpopmail account with /var/qmail/bin/sendmail (echo hi | mail -s
nothing box@domain.com) (/usr/sbin/sendmail is a symlink to
/var/qmail/bin/sendmail). all subsequent attempts from a command-line
have failed. mail destined for remote mta's seems to be working ok.

all filesystems have ample free space and free inodes. the machine is
running redhat linux 8 with a stock kernel (2.4.18-smp) and all file
systems are on raid1. other than qmail, i'm running vpopmail and
courier imap/pop. i don't know if the crashed mirror has anything to
do with this, but the symptom of failing local mail delivery happened
at the same time.

i really just need to know how to make it work again. some theory on
why it happened would be ok, but it's secondary.