kernel compile - Unable to mount root fs

[Soren Orel <soren.orel@gmail.com>]

debian lenny

I download 2.6.30-1 source
tar -xjf linux-2.6.30.1.tar.bz2
cd linux-2.6.30.1
cp /boot/config-2.6.26-2-686 ./.config
apt-get install make gcc libncurses5-dev
make menuconfig (replace M to *):

Device Drivers - Multiple device support (RAID and LVM) - Device mapper support
File systems - Ext3 journalling file system support

time make -j2
make modules_install install
update-grub

then...reboot...

"VFS: Unable to mount root fs on"

What am I missing? I still have to make more "modules to built-ins"?

thank you... :\