Can anyone tell me what this panic log means?

Two times now (a week apart), I awakened to find my mac's (dual 2.5 G5) fans running at what seemed like 100+% and the screen was black and the mac entirely unresponsive. When I forced a shutdown and restarted, I found a message that the OS had quit and the dialog offered to sent a report to Apple.

This is the panic log from last night, but it means nothing to me. Can anyone shed some light on what this might mean?

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Sun Mar 30 08:14:16 2008
panic(cpu 0 caller 0x00240698): "hfs: getcnid: unknown recordType (crp @ 0x59f7804)\n"@/SourceCache/xnu/xnu-1228.4.31/bsd/hfs/hfs_catalog.c:4079
Latest stack backtrace for cpu 0:
Backtrace:
0x00000000
backtrace terminated - unaligned frame address: 0x00007FFF

Proceeding back via exception chain:
Exception state (sv=0x60e6c000)
PC=0x90AFB060; MSR=0x0000D030; DAR=0x104E2F86; DSISR=0x40000000; LR=0x0000257C; R1=0xBFDFF9D0; XCP=0x00000030 (0xC00 - System call)

BSD process name corresponding to current thread: Unknown

Mac OS version:
9C7010

Kernel version:
Darwin Kernel Version 9.2.2: Tue Mar 4 21:23:43 PST 2008; root:xnu-1228.4.31~1/RELEASE_PPC


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And here's the one from a week ago when it did the same thing. It looks virtually the same to my untrained eye:
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Sun Mar 23 08:34:51 2008
panic(cpu 0 caller 0x00240698): "hfs: getcnid: unknown recordType (crp @ 0x4749804)\n"@/SourceCache/xnu/xnu-1228.4.31/bsd/hfs/hfs_catalog.c:4079
Latest stack backtrace for cpu 0:
Backtrace:
0x0009B478 0x0009BE1C 0x00029DD4 0x00240698 0x002435EC 0x002449E8 0x0024DD44 0x00108A3C
0x000E9E38 0x000EABA8 0x00100368 0x000F7704 0x000F7CA0 0x0030A08C 0x000B2C48 0x00000000
Proceeding back via exception chain:
Exception state (sv=0x61110280)
PC=0x90AFB060; MSR=0x0000D030; DAR=0x06B1208E; DSISR=0x42000000; LR=0x0000257C; R1=0xBFDFF9D0; XCP=0x00000030 (0xC00 - System call)

BSD process name corresponding to current thread: repair_packages

Mac OS version:
9C7010

Kernel version:
Darwin Kernel Version 9.2.2: Tue Mar 4 21:23:43 PST 2008; root:xnu-1228.4.31~1/RELEASE_PPC
System model name: PowerMac7,3

Thanks for the response. As far as I can tell, this happened after midnight and I was asleep at the time.

I have a couple of Retrospect scripts that run overnight to back up various computers throughout the house and from the Retrospect logs all I can tell is that the 11:00 pm script ran fine and the computer crashed some time after the 11:00 pm script finished at 11:18 and before the 3 am script ran.

The computer would have been idle between these two scripts.


Before I boot from another drive and check the drive, I just now ran Disk Tools > Verify to verify the Startup disk and got this error:

Performing live verification.
Checking Journaled HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Invalid key for thread record
Volume check failed.

Error: Filesystem verify or repair failed.