Octopus gemfile for octopus_sharding_example that doesn't work

Octopus gemfile

source 'http://rubygems.org'

# gem 'rails', '3.0.0.beta4'
gem 'rails', '3.0.4'

# Bundle edge Rails instead:
# gem 'rails', :git => 'git://github.com/rails/rails.git'

gem "warden", '0.10.7'
gem "devise", '1.1.rc2'
gem 'pg'
gem 'ar-octopus', :git => "git://github.com/tchandy/octopus.git", :require => "octopus"

# Use unicorn as the web server
# gem 'unicorn'

# Deploy with Capistrano
# gem 'capistrano'

# To use debugger
# gem 'ruby-debug'

# Bundle the extra gems:
# gem 'bj'
# gem 'nokogiri', '1.4.1'
# gem 'sqlite3-ruby', :require => 'sqlite3'
# gem 'aws-s3', :require => 'aws/s3'

# Bundle gems for certain environments:
# gem 'rspec', :group => :test
# group :test do
#   gem 'webrat'
# end
group :test do
  gem "rspec-rails", ">= 2.0.0.beta"
  gem 'capybara'
  gem 'database_cleaner'
  gem 'cucumber-rails'
  gem 'cucumber'
  gem 'spork'
  gem 'launchy'
end