Setting up Ruby and Rails on Mac OS X Tiger

Mac OS X Tiger already ships with ruby 1.8.2 installed.

This version of Ruby is lacking support for Readline (so interactive tools such as irb are a pain to use), and there's a small bug in the native MySQL adapter which you can work around by running:

sudo gem install fixrbconfig
sudo fixrbconfig

Alternatively, you can use Locomotive to provide a complete Ruby and Rails environment, or build it yourself from source as on other linux/unix platforms.

From here, proceed to installing Christian Werner's ODBC module.