It is the correct package, but you're wrong about 12.04 not supporting it: starting from version 3.2.0-27 the upstream commits to enable Intuos5 have been included in the Ubuntu kernel. Please purge the dkms package and test with the stock kernel.
It is the correct package, but you're wrong about 12.04 not supporting it: starting from version 3.2.0-27 the upstream commits to enable Intuos5 have been included in the Ubuntu kernel. Please purge the dkms package and test with the stock kernel.