Is there any way to boot a test kernel from a running linux system without having to install the test kernel?

I'm looking for a utility or driver which stops linux, loads a binary file into memory, and boots it. Exactly what loadlin.exe does, but from linux instead of MSDOS.

I've searched and searched and can't find any way to do this seemingly obvious thing.

The system is an embedded ARM system and boots from flash to a ramdisk so MSDOS is out of the question and getting LILO to work would be difficult. I don't want to install/flash the test kernel because recovering from a bad kernel would be very difficult since the flash utility could not be run.

Any help, pointers or alternative solutions would be very much appreciated!