I recently upgraded kernel on one of my servers from hardened-sources-2.6.28-r7 to hardened-sources-2.6.28-r9 and immediately had problems after reboot. Rebooting that server, I was greeted with the following message:
Booting 'Gentoo (bzImage-2.6.28-hardened-r9)'
root (hd0,0)
Filesystem type is ext2fs, partition type 0x83
kernel (hd0,0)/boot/bzImage-2.6.28-hardened-r9 root=/dev/sda4
[Linux-bzImaeg, setup=0x2a00, size=0x165990]
Decompressing Linux... Parsing ELF... done.
Booting the kernel.I went ahead and posted this issue to the Gentoo forum and worked on a few ideas how to remedy this. You can follow that thread here: http://forums.gentoo.org/viewtopic-p-5762324.html
I noticed that the hardened-source ChangeLog mentioned the following:

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