Comment 92 for bug 477169

UPDATES:
1) I succeeded in updating Grub with grub-install.

** Useful info for Mark **
I solved the error above substituting target=${host_mountpoint}/wubildr with the full path to wubildr.
Consider that I installed wubi in a partition different from the first partition, therefore my wubildr isn't in /host/. I don't know why the script didnt' found it anyway.

2) I've the same error of #85.
Whatever kernel option I choose I get: "Error: You need to load the kernel first".
So I press 'e', get rid of all that bunch of lines except the last two:
 linux /boot/vmlinuz-2.6.31-14-generic root=/dev/sda5 loop=/ubuntu/disks/root.disk ro single
 initrd /boot/initrd.img-2.6.31-14-generic

Try. Don't work, 'cause it seems /boot folder is empty.
So I've to substitute /boot with /boot_old (that was a copy of the old /boot folder that I made before creating boot.disk, ecc...)
And all seems to work.

My question now is: how can I tell grub to load boot.disk into /boot before loading kernel with these two commands?