I have a vmlinuz-3.2.0-rc4+ kernel file that will not load ("invalid magic number") with the latest Ubuntu grub2

[Miles Lane]

Hello,

I am running the development version of Ubuntu (12.04 - Precise).   My
machine has an Intel Core I3 processor.
I have built a kernel from Linus' GIT development tree (3.2.0-rc4+).
I am running self-built kernels on a variety of other machines, but
all my self-built kernels fail to load on this desktop.  I can,
however, boot the Ubuntu 12.04 kernels.
I tested copying my kernel file to a USB flash drive and loading it
from there using the Grub2 command line instructions.  It still failed
to load with the same error:  "invalid magic number".
This leads me to suspect that perhaps this is not a grub2 bug, but
rather a problem with my kernel build configuration options.  However,
the grub error message is so vague that I have no idea what the
configuration problem is.  What IS a magic number in this situation?
Any thoughts regarding what I should try?

Thanks!

        Miles