1.8.6 is the version of Ruby, right?
The 3rd edition of the book is now beta and the source code is
compatible with Rails 2.0.2 already.
You can specify the version when you install Rails.
sudo gem install rails -v 1.2.3 –include-dependencies
If you are new to Rails and don't wanna be confused with multiple
installations, I would suggest you uninstall Rails 2.0.2 first.
sudo gem uninstall -v 2.0.2 rails
If it's just for learning, go get Locomotive. It's a self-contained
pre-2.0 rails installation. When you're done with it, just drop the
folder in the trash.
If you also get MAMP you'll have a self-contained Mysql installation
too.
The second edition is based on Rails 1.2.3.
You can specify the version when you install Rails.
sudo gem install rails -v 1.2.3 -include-dependencies