[Grml] Booting with grub on usb-flash-pen

I have installed grml-small 0.40 on an usb flash-pen with grml2hd.

When I try to boot it grub answers root (hd1,0) Filesystem unknown, partition type 0x7

Error 17: Cannot mount selected partition

Can any of you help me with, how to identify the flash-pen in grub? I expect to make several lines in the grub/menu, and choose between them depending on, if the PC already has a sata-harddisk or a pata-harddisk.