I wonder why skeiron.org gives an error; really I've tried it many times and it works well except for in the logs to have a minor line saying about bzip but it updates fine and apps install fine too... If it isn't working for you then you have somehow managed to mangle your gpg key or not added the repo correctly...
W: GPG error: https://downloads.maemo.nokia.com ./ Release: The following signatures were invalid: KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 W: GPG error: https://downloads.maemo.nokia.com ./ Release: The following signatures were invalid: KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 W: GPG error: https://downloads.maemo.nokia.com ./ Release: The following signatures were invalid: KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 KEYEXPIRED 1349249546 W: Ignoring Provides line with DepCompareOp for package binutils W: You may want to run apt-get update to correct these problems /home/user #