HD Install :: My method to boot DSL in USB thumb drive

First of all, I downloaded usbboot.img and the iso file of version 0.63. Below are my steps to make a USB bootable DSL:

1. mount -o loop usbboot.img /mnt
2. copy everything in /mnt to the usb dumb drive root directory.
3. copy the whole directory of /cdrom/KNOPPIX to the usb dumb drive.
4. make the usb thumb drive bootable: syslinux /dev/sda1
5. reboot the computer from the thumb drive.

The computer could be booted successfully. Unfortunately, a familiar error message was prompted up and the computer halted. The error is somewhat like this:

Can't find KNOPPIX filesystems. sorry...
droping you very limited function....
....
....

What KNOPPIX filessystem is DSL looking for?
Am I right by doing steps to make DSL usb bootable?

You might want to keep an eye on this thread http://damnsmalllinux.org/cgi-bin....5;t=177

original here.