Comment 3 for bug 272527

I believe there is a workaround:
Install R (most important packages: r-base, r-devel, r-html)
Install rkward (in synaptic)
Enable pre-released and unsupported updates (you can disable them again afterwards)

Install (in synaptic): kdelibs5-dev,cmake,subversion

Now, prepare to reinstall rkward from source:
1) Get the latest source. Open a console find a suitable folder and run:

svn co https://rkward.svn.sourceforge.net/svnroot/trunk rkward

2) Make sure the compile process can find the kde libraries: run this command (important):
export PATH=$PATH:/usr/lib/kde4/bin

3) move into the folder that has the source code
(yes, that's two times 'cd rkward' if you didn't name the folder differently):
cd rkward
cd rkward

4) run the normal compile/installation commands (note: the space and 'full stop' after 'cmake' means 'current folder'):
cmake .
make
sudo make install

4) after you start rkward you may still get the error but this time you should be able to get to the 'settings' menu, choose 'configure rkward' add a new path to pluginmap field:
/usr/local/share/apps/rkward/all.pluginmap

5) caveat:
If for some reason this folder '/usr/local/share/apps/rkward/' is empty/does not exist it should be possible to copy it (including content) from a working hardy installation.