title: Problem with Ruby Gem and Sanitize
body: <p>I'm trying to install the Ruby gem sanitize. I've already installed nokogiri:</p>
  
  <pre><code>&gt;gem list nokogiri
  
  *** LOCAL GEMS ***
  
  nokogiri (1.4.0)
  </code></pre>
  
  <p>but when I try and install sanitize I get the following error:</p>
  
  <pre><code>&gt;gem install rgrove-sanitize
  ERROR:  Error installing rgrove-sanitize:
  rgrove-sanitize requires nokogiri (~&gt; 1.3.3, runtime)
  </code></pre>