I get the same error, the problem is that the package has been imported
into ubuntu without changing the program to deal with ubuntu's system,
and is instead looking for debian repositories.
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Failed getting release file http://archive.ubuntu.com/ubuntu/dists/lenny/Release
** Attachment added: Screenshot-Error when building Debian Live system.png
http://launchpadlibrarian.net/27220025/Screenshot-Error%20when%20building%20Debian%20Live%20system.png
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Failed getting release file http://archive.ubuntu.com/ubuntu/dists/lenny/Release
