Install Linux Mint Mate Desktop On Ubuntu 11.10 Oneiric Ocelot

As most of those reading this will probably know, MATE, the successful fork of GNOME2, is part of Mint 12. Since Mint is based on Ubuntu, it is possible to use Mint’s repositories on Ubuntu. This is essentially all you need to do to be able to install MATE.
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The GNOME 2 Fork 'Mate' is a desktop environment that is used in Linux Mint 12 . If you wish to use this desktop environment on Ubuntu 11.10 Oneiric Ocelot to replace your current Unity or Gnome Shell interface, then follow the instructions given below.

>> We need first to add the main Linux Mint 12 repository to your repository list. So, open the Terminal (Press Alt+F2 and type: gnome-terminal -or- Press Ctrl+Alt+T) and run this command to edit /etc/apt/sources.list:

sudo gedit /etc/apt/sources.list

At the end of the file add this line:

deb http://packages.linuxmint.com/ lisa main upstream import

Save your file and close.

Now run the following commands in the Terminal:

sudo apt-get update
sudo apt-get install linuxmint-keyring

To install the GNOME 2 Fork 'Mate' desktop, Run following commands in the Terminal:

sudo apt-get update
sudo apt-get install mint-meta-mate

Log out the current session, and at the login screen, select MATE, then login normally: