title: Coexisting spl_autoload_register and composer autoload
body: <p>I got a legacy app which use <code>spl_autload</code> in order to load classes (they have no namespace)</p>
  
  <pre><code>&lt;?php
  
  spl_autoload_extensions('.class.php,.php');
  
  set_include_path(
      $listOfDir
  );
  
  spl_autoload_register();
  
  // require composer autoloader
  // can't place that line before the call spl_autoload_register without breaking everything.
  require __DIR__ . "/../vendor/autoload.php";
  </code></pre>
  
  <p>We recently introduced <strong>composer</strong> and Symfony <code>container</code>, <code>dependency-injection</code>  and <code>config</code> component.</p>
  
  <p>What I try to achieve is to have camelcase class loaded via composer (all new classes use camel cases to identify new vs legacy code) without causing BC breaks.</p>
  
  <p><strong>Do you have clues on how to get this working ? 
  Do new classes must have a namespace ?</strong></p>
  
  <p>PS: New classes will spread accross <em>"tons"</em> of folders. The project size is 700k LOC.</p>