I experienced mysterious crashes of the netatalk daemon installed on a freeBSD8 box. The apfd was advertised with mdnsresponder, but at the moment I tried connecting to the shares, the afpd crashed. Nothing showed in the usual logs. I tried several debugging modes, but nothing seemed to give any clue where I had to find the cause of the crashes.
I took another look the /var/log directory, wondering which logfile could provide me with any clue.

Turned out that auth.log was giving information:

Feb 14 08:35:06 zaphod afpd[9740]: twist Erlkoenig.gargleblaster.org to /bin/echo "You are not welcome to use afpd from Erlkoenig.gargleblaster.org."

Aha! this ringed a bell! I recently installed denyhosts, which uses hosts.allow.

A quick look in hosts.allow gave :

# The rest of the daemons are protected.
ALL : ALL \
         : severity auth.info \
         : twist /bin/echo "You are not welcome to use %d from %h."

So adding:

#netatalk
afpd: ALL: allow

Did the trick, netatalk is working as expected again.