LibreOffice PPA in Ubuntu Natty

Greetings, all.

I’m still fairly new to Ubuntu (Natty), so this question may have a fairly simple answer, but I haven’t been able to find it yet. Is it possible to install a later distribution’s (e.g., Oneiric) current version of LibreOffice on an earlier one (e.g., Natty) via the LibreOffice PPA? If so, how?

At present, the LibreOffice PPA only brings me up to the most current version of LibreOffice listed for Natty, which is 3.4.3. If I’m reading things correctly, though, 3.4.5 is in the PPA for Oneiric.

I’d rather not receive backport updates for everything on the system, but I would like to have the most current version LibreOffice, especially now that 3.5 is available.

Just for kicks, I have tried adding the Oneiric portion of the PPA (deb http://ppa.launchpad.net/libreoffice/ppa/ubuntu oneiric main) as an additional repository. When I open the Update Manager and check for updates, I can then see what look like updates for LibreOffice from 3.4.3 to 3.4.5. But, I cannot install these updates. When I do:

sudo apt-get update
sudo apt-get upgrade

I get a message that says “The following packages have been kept back:” with a list of the LibreOffice package updates that I see in Update Manager.

Thanks so much for the thoughts and assistance.

Ubuntu 11.04 will reach end of life in October 2012, I doubt muh effort will be put into such a backport. If the packages don’t match your distribution they won’t be installed.

My suggestion would be to proceed through manual installation from the .deb packages.

Alhtough I haven’t tested the instructions lately, there is a detailed guide on how to do that here:
http://wiki.documentfoundation.org/Installing_LibreOffice_on_Linux