I can't get Cucumber to work in Windows 7

I'm going through the Rails 3 in Action eBook and they've put a lot of emphasis on testing but I can't seem to get Cucumber to work for some reason.

I keep getting a Rake aborted! Stack level too deep error when I use to rake cucumber:ok command.

Anyone know what might be causing this?

Here's my gem file:

source 'http://rubygems.org'
gem 'rails', '3.1.1.rc1'

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

gem 'sqlite3'


# Gems used only for assets and not required
# in production environments by defaul开发者_如何学Got.
group :assets do
  gem 'sass-rails', "  ~> 3.1.0"
  gem 'coffee-rails', "~> 3.1.0"
  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

group :test, :development do
  gem 'rspec-rails', '~> 2.5'
end

group :test do
  gem 'cucumber-rails'
  gem 'capybara'
  gem 'database_cleaner'
 end

---

Use

bundle exec rake cucumber:ok