Erro ao marcar todas as atualizações

[013Raptor]

No Synaptic quando eu aperto o botão para marcar todas as atualização aparece o seguinte erro:

W: Duplicate sources.list entry http://packages.medibuntu.org hardy/free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/non-free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_non-free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/non-free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_non-free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/non-free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_non-free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_free_binary-i386_Packages)
W: Duplicate sources.list entry http://packages.medibuntu.org hardy/non-free Packages (/var/lib/apt/lists/packages.medibuntu.org_dists_hardy_non-free_binary-i386_Packages)

Como arrumo isso?

[jomafras]

Veja o tópico do RC2006 : Repositórios Ubuntu7.04/7.10/8.04.

[Glauco Hass]

A mensagem de erro diz que essas entradas estão duplicadas. O tópico sugerido pelo pintinho tem várias listas de repositórios.