problema con apt-get update

[manuel alonso tarajano]

Hola lsita acabo de reinstalar mi Ubuntu y lo he hecho con Ubuntu 5.10 _Breezy Badger.

todo magnifico hsta el momento de ejecutar apt-get update

aca les envio mi el fragmento de mi sources.list (solo he descomentareado una linea)
y les envio ademas el error q me devuelve la terminal

nota: desde el firefox logro entrar al sitio q contiene el fichero "Release.gpg" y
logro visualizar el contenido del fichero , de modo q no existen probelas de config
de red o algo por el estilo.

gracias por adelantado

manuel


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deb cdrom:[Ubuntu 5.10 _Breezy Badger_ - Release i386 (20051012)]/ breezy main
restricted

## Uncomment the following two lines to fetch updated software from the network
deb http://cu.archive.ubuntu.com/ubuntu breezy main restricted
# deb-src http://cu.archive.ubuntu.com/ubuntu breezy main restricted
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root en pollux:/home/tarajano# apt-get update
Err http://cu.archive.ubuntu.com breezy Release.gpg
  Temporary failure resolving 'cu.archive.ubuntu.com'
Failed to fetch http://cu.archive.ubuntu.com/ubuntu/dists/breezy/Release.gpg 
Temporary failure resolving 'cu.archive.ubuntu.com'
Reading package lists... Done
W: Couldn't stat source package list http://cu.archive.ubuntu.com breezy/main
Packages
(/var/lib/apt/lists/cu.archive.ubuntu.com_ubuntu_dists_breezy_main_binary-i386_Packages)
- stat (2 No such file or directory)
W: Couldn't stat source package list http://cu.archive.ubuntu.com breezy/restricted
Packages
(/var/lib/apt/lists/cu.archive.ubuntu.com_ubuntu_dists_breezy_restricted_binary-i386_Packages)
- stat (2 No such file or directory)
W: You may want to run apt-get update to correct these problems
E: Some index files failed to download, they have been ignored, or old ones used
instead.
root en pollux:/home/tarajano#
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