I don't really like the default behavior of Grub in Ubuntu to continue to add all the kernel updates to my grub boot menu. I never go back and use old kernels (except by mistake) and it just crowds up my boot menu.
In the past, I have used the #howmany option in /boot/grub/menu.lst to limit this to only the most recent kernel. Now that I am using Karmic Koala though, this option no longer appears to be available due to the fact that the default bootloader is now Grub 2.
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