the version from apt-get is not up-to-date. If you want to install the latest version, you need to download and install the sources version which you find in the Download page. You will also need the latest version of the liblqr library, which you have to download from here (sources version, of course).
However, you should also uninstall the liblqr-1 and gimp-plugin-registry packages first, but beware that the gimp-plugin-registry also provides other plugins, so if you uninstall it you will be removing those as well, and if you want them back you will have to install them manually again.
The command for uninstalling is
sudo apt-get remove liblqr-1 gimp-plugin-registry
If you decide to do it, install the additional required packages first. In Ubuntu, giving this command in a terminal should do the trick:
sudo apt-get install build-essential intltool gettext libglib2.0-dev libgimp2.0-dev
Then, compile and install the liblqr library, closely following the instructions in the installation instructions page.
Then, install the plugin following tthe instructions you find here.