acc Monitor error message

[Huang wen hui]

hi,
I have DELL PE4600 server with acc driver , running 5.4 Release.
when system boot, got this message:

Mounting root from ufs:/dev/aacd0s1a
aac0: **Monitor** ID(0:02:0); Error Event [command:0x2a]
aac0: **Monitor** ID(0:02:0); Hardware Error [k:0x4,c:0x19,q:0x0]
aac0: **Monitor** ID(0:02:0); Defect List Error

The system uptime is 87 days and I do not hit any problem. Is this
message harmless?

Thanks,

-hwh