I have tried 2.6.19 and 2.6.20-rc4, without any difference.
My machine does not have a serial-port I'm afraid
I've set up remote logging (next best to a serial port I guess) over UDP, but nothing interesting in the logs, unless
Jan 25 22:53:22 couchpotato kernel: SFW2-INext-DROP-DEFLT-INV IN=eth0 OUT= MAC=mymacaddr SRC=188.8.131.52 DST=10.24.69.188 LEN=40 TOS=0x00 PREC=0x00 TTL=239 ID=15758 PROTO=TCP SPT=80 DPT=19477 WINDOW=8190 RES=0x00 ACK FIN URGP=0
is interesting (SuSE firewall).
Otherwise there is nothing reported by the kernel before the crash. That could of course be related to the fact that this is networked logging.