can't boot 2.4.X kernel

[Ruben Porras <nahoo@inicia.es>]

I need some help here, for a reason I don't know I'm unable to boot any
2.4.X kernel, including the debian's kernels. This happens since I've
tried 2.6.0test4, I think, but I'm not sure that the test kernel caused
the problem.

When I try one of them the kernel says:
VFS: Cannot open root device "hda3" or 0303
Please append a correct "root=" boot option
kernel panic: VFS: unable to mount root on 03:03

I'm lost and I would appreciate some hints to debug this.

the relevant items in the grub menu.lst are:

# this boots fine
title           Debian GNU/Linux, kernel 2.6.0
root            (hd0,0)
kernel          /vmlinuz-2.6.0 root=/dev/hda3 ro
savedefault
boot

# this doesn't boor
title           Debian GNU/Linux, kernel 2.4.23-1-686
root            (hd0,0)
kernel          /vmlinuz-2.4.23-1-686 root=/dev/hda3 ro
initrd          /initrd.img-2.4.23-1-686
savedefault
boot

I think both are fine.

Thanks.