When I made one of daily upgrades in Ubuntu 7.10 (dualboot with Fedora) something went wrong.
Next time I started the computer Fedora boot option was not in the Grub menu.
[Reason]
The /boot/grub/menu.lst is regenerated every time the kernel is updated. Moreover, we should not manually put entries between ##BEGIN DEBAIN AUTOMAGIC KERNEL LIST and ##END DEBIAN AUTOMAGIC KERNEL LIST.
[Solution]
Modify /boot/grub/menu.lst and append Fedora boot option.