This ppa contains alpha and beta release (before the 4.X.0 release) and early release candidates. Only for the most brave and courageous!

to test these do:
sudo apt-get purge libreoffice-core
sudo add-apt-repository ppa:libreoffice/libreoffice-prereleases
sudo apt-get update
sudo apt-get install libreoffice
sudo apt-get install libreoffice-l10n-zh-tw