FPU emulator: unknown prefix byte 0x00

[List Account]

When booting a 2.4.7 kernel on an old 486 sx laptop I have, I get the following error (non recoverable) when fsck is run during startup:

FPU emulator: unknown prefix byte 0x00, probably due to self-modifying code (emulation impossible)
FPU ........: internal error type 0x0126
At 00000023:0206
 SW: b=1 st=0 es=1 sf=1 cc=0010 ef=111111
 CW: ic=0 rc=00 pc=11 ien=0     ef=111111

When booting init=/bin/bash I can run some commands, but some fail, like lilo, df, fsck

The laptop is running Debian Woody
The laptop is a non-brand (Trust ?!? anybody???) 486 sx with 4mb ram and a 123mb HD

Does anybody have a clue why this laptop is not working?

thanks,
	Olivier