Apple Alerts Users of Issues With FireWire Storage:
"Following a growing number of online reports of problems when using external FireWire 800 hard drives with the recently released Mac OS X 10.3, aka Panther, Apple late Friday issued a blanket warning to users of all OS X versions. "

Posted on Apple's Web site, the "special message" said the company had identified an issue with external FireWire hard drives. It pointed to the Oxford Semiconductor Ltd.'s 922 bridge chipset with Version 1.02 firmware as the source of the problem. "In the interim, Apple recommends that you do not use these drives. To stop using the drive, you should unmount or eject the disk drive before doing anything else," the message stated.

This problem occurs with external drives using the FireWire 800 interface. All current Macs, desktops and notebooks, come either with the older FireWire 400 or faster FireWire 800 interface, or both.…

http://www.eweek.com/article2/0,4149,1369891,00.asp