These are the steps to install OpenOffice 3.1 on Ubuntu.
First of all download OpenOffice 3.1 from the official web site. When you’re done, follow these steps:
1. Remove previous version
sudo apt-get remove openoffice*.*
2. Remove settings folder
This will remove ALL your OpenOffice settings
rm ~/.openoffice.org -rf
3. Expand the archive
tar -xvzf OOo_3.1.0_LinuxIntel_install_en-US_deb.tar.gz
4. Setup
cd OOO310_m11_native_packed-4_en-US.9399/DEBS/ sudo dpkg -i *.deb
5. Setup desktop integration
cd desktop-integration sudo dpkg -i openoffice.org3.1-debian-menus_3.1-9393_all.deb
Thank you for helping me solve my dilemma with Ubuntu 9.04. I tried the regular uninstall with synaptic package manager, but I think 2 of your steps were key. Step 2 which removes ALL your Openoffice settings and Step 1, removing the previous version. The command line worked flawlessly for me. I now have Openoffice 3.10.