This additional repository is not an official part of Ubuntu. However, it is quite convenient for installing restricted pieces of software. To enable it, follow these instructions:
Launch
→ → and choose → .In the tab Third-Party Software, add the line
deb http://packages.medibuntu.org/ gutsy free non-free
In the console, type
wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O- | sudo apt-key add -
. This will make sure that the additional packages you install will really come from the correct source.
Hit Reload in Synaptic.