Compiled kernel 2.4.9 does NOT boot

[José Luis Rey <jrey@mercared.com>]

I installed kernel-image for 2.4.9 and everything went right, then I
installed kernel-source 2.4.9 copied the configuration for the kernel
from /boot/config-2.4.9-586tsc and did as allways:
   make dep
   make
   make modules
   make modules_install
   make install
   mkinitrd -o /boot/initrd-2.4.9-test /lib/modules/2.4.9-test
and added a test entry in lilo.conf with:
   image=/vmlinuz.test
        label=Test
        read-only
        initrd=/boot/initrd-2.4.9-test

The problem is that after initrd is loaded kernel panics with:
   Kernel panic: VFS: unable to mount root fs on 03:03

I'm prety shure that my root file system is in /dev/hda3, so I ran rdev
on two different kernel-images:
   vmlinuz-2.4.9-586tsc  -> 0x3a05
   vmlinuz-2.4.9-k6      -> 0x7320

I think this had to do with the devfs thing, so I re-made the kernel
without DEVFS support and ext2 in the kernel and it booted.

Does anybody knows what happens with devfs, rdev or new kernel booting
procedure ?, did I miss something from the docs ?

I know it currently works, but I've not a clue of why it doesn't work
out of box, and I'd like to understand whats wrong.

Greetings
    Jose Rey
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