cannot open bayes databases Interrupted system call

[Mike Fahey]

Every 24 hours I see the following errors and spamassassin has to be 
restarted. Other machines running SA are fine.

SA 3.2.4_1
freebsd 6.2
perl5.8.8
spamd[19777]: bayes: cannot open bayes databases 
/usr/local/share/spamassassin/bayes_* R/W: lock failed: Interrupted 
system call