title: `<module:Rails>': superclass mismatch for class Server (TypeError)
body: <p>I have seen <a href="https://stackoverflow.com/questions/9814282/typeerror-superclass-mismatch-for-class-word-ruby">this</a> and several others question, but their problems are not similar to mine.</p>
  
  <p>I have added the following code to the <code>config/boot.rb</code> , to run my server on port 8081</p>
  
  <pre><code>module Rails
    class Server
      def default_options
        super.merge({Port: 8081})
      end
    end
  end
  </code></pre>
  
  <p>Then I tried to run <code>rails s</code>, and i face with this erorr:</p>
  
  <pre><code>/usr/local/rvm/gems/ruby-2.2.1/gems/railties-4.2.4/lib/rails/commands/server.rb:7:in `&lt;module:Rails&gt;': superclass mismatch for class Server (TypeError)
          from /usr/local/rvm/gems/ruby-2.2.1/gems/railties-4.2.4/lib/rails/commands/server.rb:6:in `&lt;top (required)&gt;'
  </code></pre>