MySQL 5 crashing on 6.0

[Adam Bayless]

I've got a brand new dual AMD opteron box with 4gigs total ram running MySQL 5.0.18. 
I built MySQL from ports and I'm using /usr/local/share/mysql/my-innodb-heavy-4G.cnf 
for my.cnf. The database is accessed by 4 client machines for an sql based 
spamassassin bayes database. The bayes tables are all InnoDB. The InnoDB data file is 
about 1.1 gigs on disk right now.

MySQL is crashing and dumping a core file approximately every 4-6 hours. When it 
crashes mysqld_safe seems to be able to restart it just fine every time, but of 
course the innodb data has to be rebuilt from the logs which takes several minutes 
and processing mail stops while that happens. I thought initially that it must have 
been running into server memory limits, but I cut all of MySQL's internal limits 
approximately in half (in my.cnf) and it's still having the same trouble. There 
doesn't seem to be a certain query that causes it to crash every time, though when 
spamassassin runs a bayes expiration that sometimes seems to trigger the crash, other 
times it doesn't, though it always increases MySQL's CPU and memory usage.

I've set the following in /boot/loader.conf:

kern.maxdsiz="3684354560"
kern.dfldsiz="3684354560"
kern.maxssiz="3684354560"


'gdb -c mysqld.core' says:

Program terminated with signal 11, Segmentation fault.
#0  0x00000000dc9cf81f in ?? ()

which doesn't help me much. Maybe someone else can make some sense of that?

Any ideas?

Thanks,

Adam