Can't start rails server after 3.0.1 upgrade

Followed instructions on Railscast but can't get server to start. It states the following error:

$ rails s 
script/rails:6:in `require': no such file to load -- rails/commands (LoadError)`
from script/rails:6:in `<main>'

Saw the answer on this related question but my Gemfile has no reference to any rails 2.x version and in the "bundle install" results i get this in the results: "Using rails (3.0.1)"

EDIT: (adding Gemfile.lock details)

GEM
  remote: http://rubygems.org/
  specs:
    abstract (1.0.0)
    actionmailer (3.0.1)
      actionpack (= 3.0.1)
      mail (~> 2.2.5)
    actionpack (3.0.1)
      activemodel (= 3.0.1)
      activesupport (= 3.0.1)
      builder (~> 2.1.2)
      erubis (~> 2.6.6)
      i18n (~> 0.4.1)
      rack (~> 1.2.1)
      rack-mount (~> 0.6.12)
      rack-test (~> 0.5.4)
      tzinfo (~> 0.3.23)
    activemodel (3.0.1)
      activesupport (= 3.0.1)
      builder (~> 2.1.2)
      i18n (~> 0.4.1)
    activerecord (3.0.1)
      activemodel (= 3.0.1)
      activesupport (= 3.0.1)
      arel (~> 1.0.0)
      tzinfo (~> 0.3.23)
    activeresource (3.0.1)
      activemodel (= 3.0.1)
      activesupport (= 3.0.1)
    activesupport (3.0.1)
    arel (1.0.1)
      activesupport (~> 3.0.0)
    builder (2.1.2)
    calendar_date_select (1.16.1)
    erubis (2.6.6)
      abstract (>= 1.0.0)
    googlecharts (1.6.0)
    i18n (0.4.2)
    mail (2.2.9)
      activesupport (>= 2.3.6)
      i18n (~> 0.4.1)
      mime-types (~> 1.16)
      treetop (~> 1.4.8)
    mechanize (1.0.0)
      nokogiri (>= 1.2.1)
    mime-types (1.16)
    nokogiri (1.4.3.1)
    pg (0.9.0)
    polyglot (0.3.1)
    rack (1.2.1)
    rack-mount (0.6.13)
      rack (>= 1.0.0)
    rack-test (0.5.6)
      rack (>= 1.0)
    rails (3.0.1)
      actionmailer (= 3.0.1)
      actionpack (= 3.0.1)
      activerecord (= 3.0.1)
      activeresource (= 3.0.1)
      activesupport (= 3.0.1)
      bundler (~> 1.0.0)
      railties (= 3.0.1)
    railties (3.0.1)
      actionpack (= 3.0.1)
      activesupport (= 3.0.1)
      rake (>= 0.8.4)
      thor (~> 0.14.0)
    rake (0.8.7)
    sparklines (0.5.2)
    thor (0.14.4)
    treetop (1.4.8)
      polyglot (>= 0.3.1)
    tzinfo (0.3.2开发者_StackOverflow3)

PLATFORMS
  ruby

DEPENDENCIES
  calendar_date_select
  googlecharts
  mechanize
  pg
  rails (= 3.0.1)
  sparklines

EDIT: (adding Boot.rb details)

require 'rubygems'

# Set up gems listed in the Gemfile.
gemfile = File.expand_path('../../Gemfile', __FILE__)
begin
  ENV['BUNDLE_GEMFILE'] = gemfile
  require 'bundler'
  Bundler.setup
rescue Bundler::GemNotFound => e
  STDERR.puts e.message
  STDERR.puts "Try running `bundle install`."
  exit!
end if File.exist?(gemfile)

I had the same problem.

I fixed it just deleting the Gemfile.lock file and running from the console

bundle install

If you have problems with Bundler as well, you can install it again

gem install bundler # you may need sudo before. 

That make it work for me.

export GEM_HOME=/usr/lib/ruby1.9.1/gems/1.9.1/

Of course you'll need the appropriate path.