Preupgrade F10 to F11: Installer boot fails in GRUB

[Robert Nichols]

Running preupgrade in F10, all packages are downloaded successfully, and I click
on the "Reboot now" button.  When the system reboots, I select the "Upgrade
to
Fedora 11 (Leonidas)" entry from the GRUB menu and get an immediate "Error 15:
File not found" failure from GRUB.

Everything is on one partition (no separate /boot partition).

In /boot/grub/grub.conf:

   default=1
   timeout=10
   splashimage=(hd0,6)/boot/grub/splash.xpm.gz
   #hiddenmenu
   title Upgrade to Fedora 11 (Leonidas)
	kernel /boot/upgrade/vmlinuz preupgrade repo=hd::/var/cache/yum/preupgrade
stage2=hd:UUID=d137c2a7-7913-42ed-87b0-6b3fac3ec768:/boot/upgrade/install.img
ks=hd:UUID=d137c2a7-7913-42ed-87b0-6b3fac3ec768:/boot/upgrade/ks.cfg
	initrd /boot/upgrade/initrd.img

The filesystem has the matching UUID:
   # tune2fs -l /dev/sda7 | grep UUID
   Filesystem UUID:          d137c2a7-7913-42ed-87b0-6b3fac3ec768

In /boot/upgrade:
   total used in directory 134984 available 62504828
   drwxr-xr-x 2 root root      4096 2009-06-24 14:54 .
   drwxr-xr-x 5 root root      4096 2009-06-24 14:53 ..
   -rw-r--r-- 1 root root  18985802 2009-06-02 17:02 initrd.img
   -rw-r--r-- 1 root root 116039680 2009-06-02 17:04 install.img
   -rw-r--r-- 1 root root       276 2009-06-24 14:54 ks.cfg
   -rw-r--r-- 1 root root   3035056 2009-06-02 17:02 vmlinuz

I have no idea what file GRUB is complaining it can't find.  (Don't you just
love error messages like that?)

-- 
Bob Nichols     "NOSPAM" is really part of my email addressw.
                 Do NOT delete it.