I have been following the instructions at http://elinux.org/RPi_Kernel_Compilation to compile the 3.8 branch of the kernel from https://github.com/raspberrypi/linux/br ... 3.8.y-temp.
Both of the resulting Image and zImage in arch/arm/boot are booting up though. Using 'file' on them reports 'data', while it reports 'Linux kernel ARM boot executable zImage (little-endian)' for the original kernels? A previous 3.6 compilation worked for me, though...
On a sidetrack: Is using imagetool-uncompressed.py still necessary? The resultant kernel.img from using it on Image and zImage did not work either.