little liveCD to boot on USB-HDD without bios option

[loux.thefuture]

Hello,
is there a way to create (once for all) a little liveCD to boot my USB-HDD drive when the BIOS can not boot on USB ?
i have already made a livecd (with gentoo) and use a grub like this on it :
"
title=LiveUSB
root (cd)
kernel (cd)/boot/kernel-genkernel-x86-2.6.16-gentoo-r11 \
root=/dev/ram0 init=/linuxrc \
udev nodevfs dodmraid real_root=/dev/sda1
initrd (cd)/boot/initramfs-genkernel-x86-2.6.16-gentoo-r11
"
and i works well if my USB-HDD drive has the same kernel
but if my USB-HDD has another kernel i have trouble to use it
how can i do ?
thanks for your help
loux
_________________
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