I suspect that the cause is poor support for journalling. I created a separate HFS+ partition with journalling turned off. This time I didn't have to force rw mode, so I suspect it will be more stable. I'll post back here if it dies again.
Thanks Robbie -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
