sudo apt-get update
sudo apt-get build-dep libreoffice
sudo apt-get install git-core

cd ~/Documents
mkdir git
cd git
git clone git://anongit.freedesktop.org/libreoffice/core core
cd core

git branch -f rollback ec894c5fb90bdee1c56d113d14b0bf524df9f # create new branch named rollback starting from the commit indicated by the hash
git checkout rollback
./configure --without-junit --without-doxygen --without-mozilla
make fetch
./g checkout rollback # the wiki says to do this
make dev-install