[U-Boot-Users] Preparing linux image problem

Hi all, After built uboot and linux kernel for at91sam9rlek (refer www.linux4sam.org), I try to generate a compressed uImage file using follow command:

mkimage -A arm -O linux -C none -T kernel -a 20008000 -e 20008000 -n linux-2.6 -d arch/arm/boot/zImage uImage

but I received: "mkimage: Can't map uImage: No such device" message.

How can i fix this problem?

Thanks and best regards,