problema con apt-get update

[Ariel <ariel@cncc.cult.cu>]

hola lista recien instale wheezy y al hacer apt-get update me salen los 
siguientes errores, alguna idea al respecto:

pd: he podido instalar ya paquetes desde los repos pero me queda la duda 
que algo ande mal con esos errores.

gracias de antemano


wheezy
root@challenger:/# apt-get update
Des:1 file: wheezy Release.gpg [1.672 B]
Des:2 file: wheezy Release [167 kB]
W: Imposible obtener 
bzip2:/media/ALMACEN/repos/wheezy/wheezy/dists/wheezy/main/i18n/Translation-en.bz2  
La suma hash difiere

E: Some index files failed to download. They have been ignored, or old 
ones used instead.



wheezy-backports
Des:1 file: wheezy-backports Release.gpg [1.571 B]
Des:2 file: wheezy-backports Release [123 kB]
E: Release file for 
file:///media/ALMACEN/repos/wheezy/wheezy-backports/dists/wheezy-backports/Release 
is expired (invalid since 35d 23h 11min. 32s


wheezy-security
Des:1 file: wheezy/updates Release.gpg [836 B]
Des:2 file: wheezy/updates Release [102 kB]
E: Release file for 
file:///media/ALMACEN/repos/wheezy/wheezy-security/dists/wheezy/updates/Release 
is expired (invalid since 33d 8h 16min. 25seg.). Updates for this 
repository will not be applied.


wheezy-updates
Des:1 file: wheezy-updates Release.gpg [1.571 B]
Des:2 file: wheezy-updates Release [116 kB]
E: Release file for 
file:///media/ALMACEN/repos/wheezy/wheezy-updates/dists/wheezy-updates/Release 
is expired (invalid since 35d 23h 15min. 41seg.). Updates for this 
repository will not be applied.