Since the debian packages are signed for not forcing you to install packages from which you do not know, that any bad guy provided them, you need the public key from the person which habe signed them. Otherwise you are not able to check if the signature is valid.
So you have to find the public key that was used to sign the packages on http://archive.progeny.com and import it (how was this done?). Cheers W. Mader
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