repositories

[list at loampitsfarm.co.uk]

I've just been trying to install, using synaptic, kmail as the 
default e-mail client on a computer running xubuntu xfe. I'm getting 
the error 
message "http://gb.archive.ubuntu.com/ubuntu/pool/main/k/kdebase/kdebase-bin_3.5.6-Oubuntu20.1_i386.deb 
404 not found".

Is it possible to find another repository with this in and add it to 
sources.list?

Andrew Heggie