Probléme avec grub lors d'une double instal..

[bibi@localhost ~]$ su
Mot de passe : 
[root@localhost bibi]# grep -E '^(#|$)' /mnt/ubuntu/boot/grub/menu.lst
# menu.lst - See: grub(8), info grub, update-grub(8)
#            grub-install(8), grub-floppy(8),
#            grub-md5-crypt, /usr/share/doc/grub
#            and /usr/share/doc/grub-doc/.
## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not change this entry to 'saved' or your
# array will desync and will not let you boot your system.

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
#hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line)  and entries protected by the
# command 'lock'
# e.g. password topsecret
#      password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title         Windows 95/98/NT/2000
# root          (hd0,0)
# makeactive
# chainloader   +1
#
# title         Linux
# root          (hd0,1)
# kernel        /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
##      kopt_2_6_8=root=/dev/hdc1 ro
##      kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=da846547-e531-45d0-93ee-4a7de80d44a9 ro

## Setup crashdump menu entries
## e.g. crashdump=1
# crashdump=0

## default grub root device
## e.g. groot=(hd0,0)
# groot=(hd0,2)

## should update-grub create alternative automagic boot options
## e.g. alternative=true
##      alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
##      lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
##      lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
##      altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
##      howmany=7
# howmany=all

## should update-grub create memtest86 boot option
## e.g. memtest86=true
##      memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## ## End Default Options ##




### END DEBIAN AUTOMAGIC KERNELS LIST

# This is a divider, added to separate the menu items below from the Debian
# ones.


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/hda2.
#title          Debian GNU/Linux, kernel 2.6.17 Default (on /dev/hda2)


# This entry automatically added by the Debian installer for an existing
# linux installation on /dev/hda2.

[root@localhost bibi]# 

grep -vE '^(#|$)' /mnt/ubuntu/boot/grub/menu.lst

su [bibi@localhost ~]$ su 
Mot de passe : 
[root@localhost bibi]# grep -vE '^(#|$)' /mnt/ubuntu/boot/grub/menu.lst
splashimage=(hd0,2)/home/bibi/dunes.xpm.gz
default         0
timeout         30
title           ubuntu feisty fawn
root            (hd0,2)
kernel          /boot/vmlinuz-2.6.20-15-generic root=UUID=da846547-e531-45d0-93ee-4a7de80d44a9 ro quiet splash
initrd          /boot/initrd.img-2.6.20-15-generic
quiet
savedefault
title           ubuntu session de secour
root            (hd0,2)
kernel          /boot/vmlinuz-2.6.20-15-generic root=UUID=da846547-e531-45d0-93ee-4a7de80d44a9 ro single
initrd          /boot/initrd.img-2.6.20-15-generic
title           Ubuntu memtest86+
root            (hd0,2)
kernel          /boot/memtest86+.bin
quiet
title           Other operating systems:
root
root            (hd0,1)
kernel          /boot/vmlinuz root=/dev/hda2 ro ramdisk_size=100000 lang=fr apm=power-off nomce vga=791 
initrd          /boot/initrd.img
savedefault
boot
title           kaella-knoppix
root            (hd0,1)
kernel          /boot/vmlinuz-2.6.17 root=/dev/hda2 ro ramdisk_size=100000 lang=fr apm=power-off nomce vga=791 
initrd          /boot/initrd.img-2.6.17
savedefault
boot
[root@localhost bibi]# 

ls -l /dev/disk/by-uuid/

[root@localhost bibi]# ls -l /dev/disk/by-uuid/
total 0
lrwxrwxrwx 1 root root 10 aoû 17 12:42 25f87c9d-5ae8-4a5d-b5ac-214eff9cdce2 -> ../../sda2
lrwxrwxrwx 1 root root 10 aoû 17 12:42 93c2d7ca-8052-4f38-af20-d83a2b3dcdfe -> ../../sda1
lrwxrwxrwx 1 root root 10 aoû 17 12:42 da846547-e531-45d0-93ee-4a7de80d44a9 -> ../../sda3
[root@localhost bibi]# 

u [bibi@localhost ~]$ su 
Mot de passe : 
[root@localhost bibi]# grep -vE '^(#|$)' /mnt/ubuntu/boot/grub/menu.lst
splashimage=(hd0,2)/home/bibi/dunes.xpm.gz
default         0
timeout         30
title           ubuntu feisty fawn
root            (hd0,2)
kernel          /boot/vmlinuz-2.6.20-15-generic root=UUID=da846547-e531-45d0-93ee-4a7de80d44a9 ro quiet splash
initrd          /boot/initrd.img-2.6.20-15-generic
quiet
savedefault
title           ubuntu session de secour
root            (hd0,2)
kernel          /boot/vmlinuz-2.6.20-15-generic root=UUID=da846547-e531-45d0-93ee-4a7de80d44a9 ro single
initrd          /boot/initrd.img-2.6.20-15-generic
title           Ubuntu memtest86+
root            (hd0,2)
kernel          /boot/memtest86+.bin
quiet
title           Other operating systems:
root
root            (hd0,1)
kernel          /boot/vmlinuz root=/dev/hda2 ro ramdisk_size=100000 lang=fr apm=power-off nomce vga=791 
initrd          /boot/initrd.img
savedefault
boot
title           kaella-knoppix
root            (hd0,1)
kernel          /boot/vmlinuz-2.6.17 root=/dev/hda2 ro ramdisk_size=100000 lang=fr apm=power-off nomce vga=791 
initrd          /boot/initrd.img-2.6.17
savedefault
boot
[root@localhost bibi]# 

 reboot