In order to use my contributed packages you need configure your apt. You can do it by adding:

  deb http://gsd.di.uminho.pt/members/los/ubuntu feisty contrib

and:

  deb-src http://gsd.di.uminho.pt/members/los/ubuntu feisty contrib

to your:

  /etc/apt/sources.list

Do not forget to import my gpg key:

  wget -q -O - http://gsd.di.uminho.pt/members/los/los.asc | sudo apt-key add -

Have fun!