Thanks for the reply.. I'm not sure kexec is what I'm after though. Isn't it for booting into a new kernel when one kernel is already running?

I'm afraid I don't know very much about Maemo, though I am reasonably ok with "normal" linux, so can I explain it like this? I would like something like a grub or lilo bootloader, so that I can choose a different kernel at boot time, but without reflashing the device, and boot into the existing filesystem.

"bootmenu" sounds like it might do this, but maybe bootmenu depends on kexec in some way I didn't understand?

Edit: Oh, hold on, I think I get it.. bootmenu is really for switching the mounts and init processes at boot-time, not for running a different kernel, right? I was thinking too much in terms of standard linux bootloaders. And hence, you would indeed need kexec to get a different kernel running...