The release of Ubuntu 11.10 (Oneiric) brings much-needed updates to the Ruby packaging. We can now get a sane Ruby environment in Ubuntu with a few commands.
sudo apt-get install ruby1.9.1-full
sudo update-alternatives --set ruby /usr/bin/ruby1.9.1
sudo env REALLY_GEM_UPDATE_SYSTEM=1 gem update --system
This sets up a fully working MRI 1.9.2 environment, with an up-to-date version of Rubygems.
Enjoy!
