[Grml] How to use the .iso image for usb booting

Hi,

How can I put the .iso image on usb so that the usb boots with the latest devel release, grml-medium-devel_2008.09.28.iso for example?

The wiki http://wiki.grml.org/doku.php?id=usb & grml2usb uses windoze FAT16 filesystem, but I hope I can put it into (and boot from) native Linux filesystems, using grub if possible.

thanks