I'm trying to make a bootable USB flash with fedora 6.

I select the kernel via grub to boot which is fine. Here
is a screen output(I had to hand copy so it does not have all details but the relevant ones)

kernel /vmlinux-2.6.20-1.2948.fc6
..
initrd /initrd-2.6.20-1.2948.fc6.img
..

Uncompressing Linux...OK, boot the kernel.
RedHat nash version 5.1.19.03 starting

sda: assuming drive cache: write through
..
setuproot: moving /dev/failed: No such file or directory

-------------------------------------------------
I created the RAM disk using the following command line:
********************************************************
./mkinitrd --preload usb-storage --preload ehci-hcd --preload scsi_mod --preload sd_mod initrd-2.6.20-1.2948.fc6.img 2.6.20-1.2948.fc6

Content of initrd-2.6.20-1.2948.fc6.img:
****************************************
bin/ dev/ etc/ init* lib/ proc/ sbin@ sys/ sysroot/
----------------------------------------------------

fstab :
*******

LABEL=/ / ext3 defaults 1 1
LABEL=/boot /boot ext3 defaults 1 2
/dev/sda3 swap swap defaults 0 0

-------------------------------------------------
Here is the partition info :
*******************************

Disk /dev/sda: 948 cylinders, 129 heads, 32 sectors/track
Units = cylinders of 2113536 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/sda1 * 0+ 47 48- 99056 83 Linux
/dev/sda2 48 237 190 392160 83 Linux
/dev/sda3 238 475 238 491232 82 Linux swap / Solaris
/dev/sda4 0 - 0 0 0 Empty

--------------------------------------------
Here is a file listing of /dev/sda1(/boot)
***********************************

config-2.6.20-1.2948.fc6 symvers-2.6.20-1.2948.fc6.gz
grub System.map-2.6.20-1.2948.fc6
initrd-2.6.20-1.2948.fc6.img vmlinuz-2.6.20-1.2948.fc6
lost+found

----------------------------------------------

/dev/ is not found. The RAM disk file is located in /boot. /dev is present in initrd-2.6.20-1.2948.fc6.img.

Why cannot the /dev/ directory be found?

--thanks