Je ne vois pas bien en quoi mon sources.list aurait quelque chose à voir là-dedans... mais le voici :
/etc/apt/sources.list :
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://be.archive.ubuntu.com/ubuntu/ feisty main restricted
deb-src http://be.archive.ubuntu.com/ubuntu/ feisty main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://be.archive.ubuntu.com/ubuntu/ feisty-updates main restricted
deb-src http://be.archive.ubuntu.com/ubuntu/ feisty-updates main restricted
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://be.archive.ubuntu.com/ubuntu/ feisty universe
deb-src http://be.archive.ubuntu.com/ubuntu/ feisty universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://be.archive.ubuntu.com/ubuntu/ feisty multiverse
deb-src http://be.archive.ubuntu.com/ubuntu/ feisty multiverse
## Uncomment the following two lines to add software from the 'backports'
## repository.
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
# deb http://be.archive.ubuntu.com/ubuntu/ feisty-backports main restricted universe multiverse
# deb-src http://be.archive.ubuntu.com/ubuntu/ feisty-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu feisty-security main restricted
deb-src http://security.ubuntu.com/ubuntu feisty-security main restricted
deb http://security.ubuntu.com/ubuntu feisty-security universe
deb-src http://security.ubuntu.com/ubuntu feisty-security universe
deb http://security.ubuntu.com/ubuntu feisty-security multiverse
deb-src http://security.ubuntu.com/ubuntu feisty-security multiverse
/etc/apt/sources.list.d/universe.list :
# UNIVERSE MULTIVERSE
## SERVEURS FRANÇAIS
deb http://fr.archive.ubuntu.com/ubuntu/ feisty main restricted universe multiverse
deb http://fr.archive.ubuntu.com/ubuntu/ feisty-security main restricted universe multiverse
deb http://fr.archive.ubuntu.com/ubuntu/ feisty-updates main restricted universe multiverse
# Sources
deb-src http://fr.archive.ubuntu.com/ubuntu/ feisty main restricted universe multiverse
deb-src http://fr.archive.ubuntu.com/ubuntu/ feisty-security main restricted universe multiverse
deb-src http://fr.archive.ubuntu.com/ubuntu/ feisty-updates main restricted universe multiverse
## SERVEURS INTERNATIONAUX
deb http://archive.ubuntu.com/ubuntu/ feisty main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ feisty-security main restricted universe multiverse
deb http://archive.ubuntu.com/ubuntu/ feisty-updates main restricted universe multiverse
# Sources
deb-src http://archive.ubuntu.com/ubuntu/ feisty main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ feisty-updates main restricted universe multiverse
deb-src http://archive.ubuntu.com/ubuntu/ feisty-security main restricted universe multiverse
/etc/apt/sources.list.d/medibuntu.list :
# MEDIBUNTU
deb http://medibuntu.sos-sts.com/repo/ feisty free non-free
# Sources
deb-src http://medibuntu.sos-sts.com/repo/ feisty free non-free
