I have seen this error on a system with a Nehalem server motherboard. When it happens, the system freezes and will eventually reboot.
The full error is:
Processor /CATERR (#0x68) Informational event: CATERR reports it has been deasserted. BMC - LUN #0 (Channel #00h)
If you don't know anything about this exact error, I would still like to understand exactly what a "CATERR" is.
I should mention that the server is running a custom linux kernel based off 2.6.18.