OOPS: kernel BUG at mm/vmscan.c:606

Version: 2.6.15-27.48 for K7
Dapper Drake kubuntu

HW config:
AMD Athlon XP 2800+
Gigabyte 7nnxp motherboard
2 GB RAM
2 swap partitions, 1 GB each

At the time of OOPS, active (and memory intensive) applications:
Azureus 2.5.0.0 downloading about 1.5 GB of stuff
mplayer 0.99+1.0pre7try2+cvs20060117-0ubuntu8

The system froze in the middle of an ICQ session, while mplayer was paused, but azureus was running in GUI mode. I'm not sure if I can give any steps to reproduce the problem, but if it happens again in the same manner, I'll copy the OOPS again. I don't have any info on the swap usage at that moment.

OOPS:

kernel BUG at mm/vmscan.c:606!
invalid operand: 0000 [#1]
PREEMPT SMP
Modules linked in: nls_cp437 isofs udf iptable_filter af_packet appletalk ax25 ipx bluetooth binfmt_misc ipt_ULOG ip_tables ipv6 cpufreq_userspace cpufreq_stats freq_table cpufreq_powersave cpuf req_ondemand cpufreq_conservative video tc1100_wmi sony_acpi pcc_acpi hotkey dev_acpi container button acpi_sbs battery ac i2c_acpi_ec lp cinergyT2 cx88_blackbird cx88_dvb cx8802 mt352 or51132 video_buf_dvb dvb_core tsdev tuner cx8800 cx88xx i2c_algo_bit usbhid e1000 video_buf nxt200x ir_common tveeprom v4l1_compat v4l2_common btcx_risc videodev lgdt330x cx22702 dvb_pll i2c_nforce2 floppy parport_pc parport nvidia i2c_core snd_intel8x0 snd_ac97_codec snd_ac97_bus snd_pcm_oss snd_mixer_oss snd_pcm snd_timer psmouse pcspkr snd soundcore snd_page_alloc serio_raw forcedeth shpchp pci_hotplug nvidia_agp agpgart sg evdev ext3 jbd ide_generic ehci_hcd ohci_hcd usbcore ide_cd cdrom generic amd74xx sata_nv sd_mod sata_sil libata scsi_mod
thermal processor fan capability commoncap
CPU: 0
EIP: 0060:[isolate_lru_pages+59/176] Tainted: P VLI
EFLAGS: 00210046 (2.6.15-27-k7)
EIP is at isolate_lru_pages+0x3b/0xb0
eax: 00000000 ebx: c0357010 ecx: c1010960 edx: c0357010
esi: 00000006 edi: dfe0ff0c ebp: 00000005 esp: dfe0fe98
ds: 007b es: 007b ss: 0068
Process kswapd0 (pid: 157, threadinfo=dfe0e000 task=dffeb050)
Stack: 00000000 c0356d00 c0357000 dfe0ff0c c015cb0a 00000020 c0357010 dfe0ff0c
        dfe0ff14 c0357008 c0357010 00000020 dfe0e000 00000000 00000001 c1000dec
        c1010620 c1010644 c1010668 c101068c c10108f0 c1010914 c1010938 c101095c
Code: 46 8d 46 ff 39 44 24 14 7e 6b 3b 1b 74 67 8b 4b 04 8b 41 04 39 c3 74 07 83 e8 1c 0f 0d 08 90 90 0f ba 71 e4 05 19 c0 85 c0 75 08 <0f> 0b 5e 02 49 1f 32 c0 8b 11 8b 41 04 89 42 04 89 10 c7 41 04
Call Trace:
[shrink_cache+154/688] shrink_cache+0x9a/0x2b0
[shrink_zone+150/240] shrink_zone+0x96/0xf0
[balance_pgdat+503/1040] balance_pgdat+0x1f7/0x410
[kswapd+230/320] kswapd+0xe6/0x140
[autoremove_wake_function+0/96] autoremove_wake_function+0x0/0x60
[kswapd+0/320] kswapd+0x0/0x140
[kernel_thread_helper+5/12] kernel_thread_helper+0x5/0xc
<6>note: kswapd0[157] exited with preempt_count 1