Ruby 1.8.*, UTF-8 and Oracle / Oracle Enhanced / OCI-8

... is a mess.

For future reference:

1. Check select value from nls_database_parameters where parameter = 'NLS_CHARACTERSET'; is AMERICAN_AMERICA.AL32UTF8 or similar
2. In your boot.rb, prior to any gems being loaded, add

   require 'rubygems'
   
   # Set up gems listed in the Gemfile.
   ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
   ENV['NLS_LANG'] = 'AMERICAN_AMERICA.AL32UTF8'
   
   require 'bundler/setup' if File.exists?(ENV['BUNDLE_GEMFILE'])
   

3. Curse repeatedly at Oracle's database wide character sets, rather than MySQL's table based character sets - if you are migrating, you have to migrate every schema being used.
4. Export your data, change the character set by ALTER DATABASE CHARACTER SET, re-import.