Swap error message I've seen in 2.4.5-ac17

Yep, me again. I've been playing around with ac17 on my old 486 machine
for a few days (it seems strange that the 486 works fine while the K6
doesn't, but I digress) and I noticed today something that made my hair
stand on end:

Jun 26 16:17:27 debian kernel: VM: Bad swap entry 0033da00
Jun 26 16:17:27 debian kernel: Unused swap offset entry in swap_count
0033da00
Jun 26 16:17:27 debian kernel: Unused swap offset entry in swap_count
0033da00
Jun 26 16:38:16 debian -- MARK --
Jun 26 16:53:13 debian kernel: PPP BSD Compression module registered
Jun 26 16:53:14 debian kernel: PPP Deflate Compression module registered
Jun 26 16:53:24 debian kernel: VM: Bad swap entry 0033da00

Now I have been told by Rik Van Riel that this is a kernel bug - I
initially figured it was a bad disk, thanks to him I can breathe now...

Anyway, at the time the kernel did these messages I was just stopping
playing quake on my K6-III (486 handles packets to/from the modem) and
was reloading the compression modules, changing the mtu of my modem's 
interface to 1500 from 576, and starting fetchmail. And about one
minute later I decided to simply disconnect.

I can't seem to find a way to reproduce this problem all the time like I
can with the freezing bug, but I will reply to this thread if I see it
again and/or can repeatedly reproduce it.