-$(prepare_grub_to_access_device ${GRUB_DEVICE_BOOT} | sed -e "s/^/ /")
- iso_path="${rel_dirname}/$grml $CUSTOM_BOOTOPTIONS"
+$(prepare_grub_to_access_device $(${grub_probe} -t device ${grmliso}) | sed -e "s/^/ /")
+ iso_path="${rel_dirname}/${grml}"