Grub2 booting iso with casper-rw on newer upgraded kernels

[Goh Lip]

I have been booting livecd iso using loopback and have a partition, 
casper-rw and by adding 'persistent rw' to the linux line, any changes 
and installed applications can 'stick'. It is great that I can do this 
to test experimental OS's.

However, I have a problem trying to figure out how to ensure that any 
kernel upgrade can also stick instead of booting to the original livecd 
kernel. I noted that newer kernels are correctly added to 
/casper-rw/boot/ and correctly sys-linked to /casper-rw as /vmlinuz and 
/initrd.img. Modifying various parameters at grub2 does not seem to 
work. Is trying to boot new kernels of iso files an impossibility? 
Thought I'll ask here first before giving up.


An example of an unmodified grub menuentry as follows.....

menuentry "Livecd  " {
        loopback loop (hd0,9)/pop/Apps/kubuntu-9.10-desktop-amd64.iso
	linux (loop)/casper/vmlinuz boot=casper 
iso-scan/filename=/pop/Apps/kubuntu-9.10-desktop-amd64.iso persistent rw 
noprompt noeject quiet splash
        initrd (loop)/casper/initrd.lz
}

Please advise what needed to be changed to effect booting to new kernel.
Would also appreciate some feedback if this is impossible.


Thanks and regards - Goh Lip