LinuxQuestions.org - grub2 unable to detect iso files

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grub2 unable to detect iso files

I want to install distro directly from iso
and came to know that this can be done using grub2
so ,i installed grub2 in fedora 14 and
In /etc/grub.d
pasted the following lines in

40_custom
------------------------------

#!/bin/sh
echo "Install" >&2
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries. Simply type the
# menu entries you want to add after this comment. Be careful not to change
# the 'exec tail' line above.

menuentry "Install" {
set isofile=/casper/linuxmint-10-gnome-dvd-i386.iso
loopback loop(hd0,7)$isofile
linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile noprompt noeject
initrd (loop)/casper/initrd.lz
}

--------------------------

then ,i typed :
update-grub2
at terminal
then i rebooted and got INSTALL at grub2(1.98) menu,then

error:
file name required
no such device
kernel should be loaded first

what shall i do ?

system information

Fedora
Release 14(laughlin)
Kernel linux 2.6.35.10-74.fc14.i686
Gnome 2.32.0

For reference here is my grub.cfg for booting a ubuntu iso(s)

Code:

menuentry "Natty 11.04" {

        insmod ext2

        set root=(hd0,4)

        search --no-floppy --fs-uuid --set 72612744-7f39-486c-8ec0-f9078ab1bb41

        loopback loop (hd0,4)/Natty/natty-desktop-i386.iso

        linux (loop)/casper/vmlinuz boot=casper noprompt noeject preseed=/cdrom/preseed/xubuntu.seed iso-scan/filename=/Natty/natty-desktop-i386.iso

        initrd (loop)/casper/initrd.lz

}