title: Why isn't express-js setting the Content-Type header?
body: <p>I have the following:</p>
  
  <pre><code>var express = require('express'),
      app = express.createServer();
  
  app.get("/offline.manifest", function(req, res){
    res.contentType("text/cache-manifest");
    res.end("CACHE MANIFEST");
  });
  
  app.listen(8561);
  </code></pre>
  
  <p>The network tab in Chrome says it's <code>text/plain</code>. Why isn't it setting the header?</p>
  
  <p><em>The code above works, my problems were caused by a linking to an old version of express-js</em></p>