ruby - アクティブなリソースジェムを追加できません

Question

bundle installコマンドを実行すると、このエラーが発生します

Bundler は gem "activesupport" の互換バージョンを見つけられませんでした: Gemfile 内: activeresource (>= 0) ruby​​ は activesupport (= 2.0.1) ruby​​ に依存します

rails (= 4.0.0.rc1) ruby depends on
  activesupport (4.0.0.rc1)

これは私の宝石ファイルです

source 'https://rubygems.org'
ruby '1.9.3'

# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
gem 'rails', '4.0.0.rc1'

# Use sqlite3 as the database for Active Record
gem 'sqlite3'

# Use SCSS for stylesheets
gem 'sass-rails', '~> 4.0.0.rc1'

# Use Uglifier as compressor for JavaScript assets
gem 'uglifier', '>= 1.3.0'

# Use CoffeeScript for .js.coffee assets and views
gem 'coffee-rails', '~> 4.0.0'

# See https://github.com/sstephenson/execjs#readme for more supported runtimes
# gem 'therubyracer', platforms: :ruby

# Use jquery as the JavaScript library
gem 'jquery-rails'

# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
gem 'turbolinks'

# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
gem 'jbuilder', '~> 1.0.1'

group :doc do
  # bundle exec rake doc:rails generates the API under doc/api.
  gem 'sdoc', require: false
end

# Use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

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

# Use Capistrano for deployment
# gem 'capistrano', group: :development

# Use debugger
# gem 'debugger', group: [:development, :test]

gem 'execjs'
gem 'therubyracer'
gem 'pg'
gem 'activeresource', :require => 'active_resource'

Ruby => ruby​​ 1.9.3p429 (2013-05-15 リビジョン 40747) [x86_64-linux]

レール => レール 4.0.0.rc1

助けてください！