title: bundle install gives undefined method `ruby' for #<Bundler::Dsl:0x00000001c4e1f8>
body: <p><code>bundle install</code> is giving:</p>
  
  <pre><code>&gt; undefined method `ruby' for #&lt;Bundler::Dsl:0x00000001c4e1f8&gt;
  </code></pre>
  
  <p>Any idea how to fix? I'm using Ruby 1.9.3-p125.</p>