Aprire un terminale e:
sudo apt-get remove --purge openoffice*.*
sudo add-apt-repository ppa:libreoffice/ppa
sudo apt-get update
sudo apt-get install libreoffice libreoffice-l10n-it libreoffice-help-it
Gnome:
sudo apt-get install libreoffice-gnome
KDE:
sudo apt-get install libreoffice-kde