Cannot mount root device

[Budai Laszlo <lbudai@ms.sapientia.ro>]

Hello,

I get into trouble when I try to compile a new kernel on a 
Fujitsu-Siemens B120 computer with Fedora Core 1. The problem was the 
same with Redhat Linux 9 too.

So, I'm doing make mrproper, make menuconfig (select the options I 
need), make, make bzImage, make modules, make modules_install, make 
install. I got no errors during the compile.
When I reboot the machine with the new kernel I get the following message:

VFS: Cannot open root device "sda3" or unknown-block (0,0)
Please append a correct "root=" option
Kernel panic: VFS: unable to mount root fs on unknown-block (0,0)

the same problem is happening if I try a binary kernel downloaded from 
rawhide.

what can be done?

Thank you,
Laszlo


my lilo.conf looks like:

prompt
timeout=50
default=linux
boot=/dev/sda
map=/boot/map
install=/boot/boot.b
linear

image=/boot/vmlinuz-2.6.2
         label=linux-2.6.2
         initrd=/boot/initrd-2.6.2.img
         read-only
         append="root=/dev/sda3"

image=/boot/vmlinuz-2.4.22-1.2115.nptl
         label=linux
         initrd=/boot/initrd-2.4.22-1.2115.nptl.img
         read-only
         append="rhgb root=LABEL=/"

image=/boot/vmlinuz-2.6.1-1.65
         label=2.6.1-1.65
         initrd=/boot/initrd-2.6.1-1.65.img
         read-only
         append="rhgb root=LABEL=/"