title: heroku crashes with JSON error
body: <p>I am going through the <a href="http://ruby.railstutorial.org/ruby-on-rails-tutorial-book#sec%3adeploying" rel="nofollow">rails tutorial from railstutorial.org</a> and I have hit a stumbling block.</p>
  
  <p>My versions are thus:</p>
  
  <ul>
  <li>ruby 1.8.7 (2011-02-18 patchlevel
  334) [i386-mingw32] </li>
  <li>Rails 3.0.4</li>
  <li>heroku 1.18.2 </li>
  <li>sqlite3 3.7.3 </li>
  <li>git version 1.7.3.1.msysgit.0</li>
  </ul>
  
  <p>I get this error when I run any heroku command (heroku create, heroku keys:add etc.) </p>
  
  <pre><code>C:/RailsInstaller/Ruby1.8.7/lib/ruby/gems/1.8/gems/json-1.5.1-x86-mingw32/lib/js
  on/ext/parser.so: [BUG] Segmentation fault
  ruby 1.8.7 (2011-02-18 patchlevel 334) [i386-mingw32]
  </code></pre>
  
  <p>I noticed that some people were talking about incompatibility between heroku and json, so I uninstalled json 1.5.1 and installed json 1.4.6 instead.</p>
  
  <p>I then get the error:</p>
  
  <pre><code>C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:861:in `report_ac
  tivate_error': RubyGem version error: json(1.4.6 not ~&gt; 1.5.1) (Gem::LoadError)
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:255:
  in `activate'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:290:
  in `activate'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:289:
  in `each'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:289:
  in `activate'
          from C:/RailsInstaller/Ruby1.8.7/lib/ruby/site_ruby/1.8/rubygems.rb:1204
  :in `gem'
          from C:/RailsInstaller/Ruby1.8.7/bin/heroku:18
  </code></pre>
  
  <p>Any ideas? Thanks</p>