cannot boot from usb stick

[tindal at debianizzati.org (tindal)]

I'm currently testing the latest DLS (kde version) and I would find very 
useful to boot it from my usb stick, but I tried without success.

I currently can boot a remastered knoppix from the stick, and grub works 
magnifically.

I set up the stick (1 GB) with 3 partitions: in the first there's the 
/boot dir for grub and all the kernels and initrds I need, in the third 
there's the knoppix structure, and I use the second for saving files and 
configs.

now I copied the kernel and initrd from the DLS image to the /boot dir, 
and the casper dir with the rootfs in the second partition, but at the 
boot I get "Begin: Waiting for root filesystem... ..."

clearly it can't find the fs: I thought I needed an option by which to 
tell the kernel where to find the rootfs, and I tried with boot=casper 
(copied from isolinux.cfg), root=/dev/ram0, BOOT=usb (from an old post 
in this list), root=/dev/sda2 (this doesn't have much sense, indeed),but 
none works.

has anyone any idea?

thanks in advice, and sorry for my bad english
tindal

ps.
great work :-)
I love this project, and when I'll be graduate I think I'll find some 
time to help in some way.