HOWTO: Upgrade your Ruby on Rails install to version 2.0 on Leopard (Mac OSX 10.5)
This one’s real easy. Leopard ships with a default Rails installation (/usr/bin/rails), but overriding it is quite simple, since it’s just a gem.
sudo gem install rails --source http://gems.rubyonrails.org
Then, enter “y” at each prompt, to install all of the dependencies. That’s it! Check yourself with:
rails -v
Right now it will show Rails 1.99.0 which is the current release candidate. When rails goes fully 2.0, the same instructions should work to get the full release installed.
And don’t forget, you can always rake rails:freeze to lock a Rails app to a particular version of Rails by copying all of the Rails libraries into the /vendor directory.
Happy coding!
Houttuynia cordata (Saururaceae); Dokudami (毒痛み, ドクダミ)

Thanks for sharing this