PLF Update

At some point, the PLF site moved so you will need to update the repository location and the key.

The new site (Medibuntu) is located here. So you will need to delete the APT line and key for the old PLF repository and add the new one. The new apt line is:

deb http://medibuntu.sos-sts.com/repo/ edgy free non-free

There are instruction on how to add this new repository on the medibuntu site under Repository Howto, but to add this line for synaptic the non-command line way, go to:
System-->Administration-->Synaptic-->Settings-->Repositories-->Third Party Tab-->Click on Add-->Paste in the apt line from above.

For the key, you can use the instructions on the Medibuntu site or do it my way by right clicking on the site below and choose save link location:
Medibuntu key
Then go System-->Administration-->Synaptic-->Settings-->Repositories-->Authentication Tab-->Click on Import Key File-->Choose the file that you just downloaded.

UPDATE FOR FEISTY: The above is still true for feisty, however, the new apt line is:
deb http://medibuntu.sos-sts.com/repo/ feisty free non-free