Kernel Panics: Corrupt Skip Lists

Question

I recently upgraded my eMac's hard drive to a 160 GB hard drive. Before my eMac was very stable. I experienced maybe one or two kernel panics before upgrading. Now, they are a frequent experience. The curious thing is that all report the same error- "Corrupt Skip Lists". Yet, I cannot find any reference to this error anywhere. Also, I was running Panther before upgrading and switched to Tiger after installing the new drive. I suppose this could also be a factor. The odd thing is that these occur even when it's not running (has booted) off the new internal drive sometimes.
Here are some screen shots I've taken:
http://gamoe.net/imagebank/Other/eMacError/KernelPanic1.jpg
http://gamoe.net/imagebank/Other/eMacError/KernelPanic2.jpg
Any clues on this?

Answer 1

Interesting. A topic probably only for the more technically minded. Thank you for your response. I hadn't gotten any leads until now, even though I've posted about this elsewhere. Of course I added more RAM, it's the only decent thing to do, given Apple's traditional skimping on built-in/included RAM.
So I did as you suggested. I dug up the Apple Hardware Test CD, but it came up with nothing. I then downloaded and ran Memtest in the suggested single user mode under root. I had no idea it would take as long as it did, though I should have known, as it is an thorough test. I used the default suggested 3 passes. Results are as follows.
Test 1 gave me:
Bit Flip: FAILURE: 0xfffff3ff != 0xfffff7ff at offset 0x02c53b8b.
Test 3 gave me:
Stuck Address: FAILURE: possible bad address line at offset 0x00e52b8b.
Resulting in these conclusions:
* Address Test Failed * One or more DIMM address lines are non-functional.
* Memory Test Failed * Please check logfile for details.
Actually, I really have had no way of knowing if it was the hard drive or not. When I upgraded I also switched to Tiger, so it could be either. I must say that I am more a little surprised at the results, given that I installed this memory almost immediately after I bought the eMac, and it is Crucial RAM, which is known for quality, and it is the same RAM Apple uses for Macs. I've had absolutely no problems like this in the two years plus I've been using my eMac, under different versions of Mac OS X.
Given these results, can one reasonably conclude that the memory is responsible for the kernel panics? And, provided that the eMac has panicked even when it has not been booted up from the new internal drive, would you completely rule out the internal hard drive as the cause?-- Or can there be more to this?