title: $_SERVER[HTTP_CACHE_CONTROL] set to NO CACHE always even though cache on
body: <p>I checked <code>$_SERVER['HTTP_CACHE_CONTROL']</code> and it is saying <code>no cache</code> even though i have the meta tag:</p>
  
  <pre><code>&lt;meta http-equiv="Cache-control" content="public"&gt;
  </code></pre>
  
  <p>and I've tried this as well</p>
  
  <pre><code>&lt;meta http-equiv="Cache-control" content="cache"&gt;
  </code></pre>
  
  <p>still saying same "No CACHE"</p>
  
  <p>Should I be worried that search engine spider gets same value as <code>$_SERVER</code>?</p>