rvm would not work on ubuntu. they take pride in their Synaptic Package Manager.
last time I installed rails (2.3.8) on my unubtu 10.4 lts, I installed them using the `sudo apt-get <package-name>' commands
No, don't do that, it is much better in my opinion to use rvm, which
definitely does work on Ubuntu. Then you have the flexibility of
gemsets, mutliple ruby versions and so on.