title: Make IE cache the resources but always revalidate
body: <p>The cache control header "no-cache, must-revalidate, private" allows browsers to cache the resource but forces a revalidate with conditional requests. This works as expected in FF, Safari, and Chrome.</p>
  
  <p>However, IE7+8 does not send a conditional request, that is, "If-Modified-Since" is missing in the request header and hence the server responds with HTTP/200 instead of HTTP/304.</p>
  
  <p>Here are the full server response headers:</p>
  
  <pre><code>Last-Modified: Wed, 16 Feb 2011 13:52:26 GMT
  Content-type: text/html;charset=utf-8
  Content-Length: 10835
  Date: Wed, 16 Feb 2011 13:52:26 GMT
  Connection: keep-alive
  Cache-Control: no-cache, must-revalidate, private
  </code></pre>
  
  <p>This seems like an IE bug, but I haven't found anything related on the web, so I wonder whether maybe the absence or existence of another header makes IE behave strangely?</p>
  
  <p>A good discussion of the difference between no-cache and max-age: <a href="https://stackoverflow.com/questions/1046966/whats-the-difference-between-cache-control-max-age-0-and-no-cache">What&#39;s the difference between Cache-Control: max-age=0 and no-cache?</a></p>