I use Linux Mint 10 KDE edition but this should work equally well for Kubuntu MM. I was rooting around for the easiest way to do it and I haven't found anything simpler so far.
sudo apt-get remove openoffice*.* /Remove Open Office if installed
sudo add-apt-repository ppa:libreoffice/ppa /Add Libre Office PPA
sudo apt-get update /Update sources
sudo apt-get install libreoffice /Install Libre Office
sudo apt-get remove openoffice*.* /Remove Open Office if installed
sudo add-apt-repository ppa:libreoffice/ppa /Add Libre Office PPA
sudo apt-get update /Update sources
sudo apt-get install libreoffice /Install Libre Office
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