Rails 3.2.3 - Bundler could not find compatible versions for gem "railties"

I am tracking along with an updated version of Michael Hartl's “Ruby on Rails Tutorial” , and I encountered a bug in the “git push heroku master” step. The error generated by GIT bash is as follows:

 $git push heroku master
 Counting objects: 70, done

 ...

 Fetching gem metadata from https://rubygems.org/.........

 Bundler could not find compatible version for gem "railties":
 In Gemfile:
 rails (= 3.2.3) ruby depends on
 railties (= 3.2.3) ruby
 jquery-rails (= 2.0.0) ruby depends on
 railties (3.2.4.rc1)

In addition, the Gemfile is used here:

    source 'https://rubygems.org'

    gem 'rails', '3.2.3'

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

    group :development do
      gem 'sqlite3', '1.3.5'
    end


    # Gems used only for assets and not required
    # in production environments by default.
    group :assets do
      gem 'sass-rails',   '3.2.4'
      gem 'coffee-rails', '3.2.2'

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

      gem 'uglifier', '1.2.3'
    end

    gem 'jquery-rails', '2.0.0'

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

    # To use Jbuilder templates for JSON
    # gem 'jbuilder'

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

    # Deploy with Capistrano
    # gem 'capistrano'

    # To use debugger
    # gem 'ruby-debug19', :require => 'ruby-debug'

The only debugging instructions I could find related to Ruby versions that were different from the version used in the tutorial (that is, versions that were not 3.2.3), so any help would be greatly appreciated. Thanks in advance!