[pure:dyne] problem installing pure:dyne as main system

[Peter O'Doherty]

Hi,
I'm trying to install pure:dyne as the main system on my laptop. I've 
followed the instructions at this page exactly:

http://code.goto10.org/projects/puredyne/wiki/AptSettings

However, when I do:

aptitude show puredyne

I get:

Unable to find an archive "lenny" for the package "puredyne"
Package: puredyne
State: not a real package

Any help would be appreciated.
Thanks,
Peter

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