title: PHP Parse error - unexpected T_STRING
body: <p>In Windows (WAMP) I have an index.php like this</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;?php
      // ...
  ?&gt;
  </code></pre>
  
  <p>and it works as expected.<br>
  Now I've just configured a LAMP on Ubuntu and the same file (when invoked from a browser) gives me an error. Looking in <code>error.log</code> I've found </p>
  
  <blockquote>
    <p>PHP Parse error:  syntax error, unexpected T_STRING in
    /var/www/test/index.php on line 1</p>
  </blockquote>
  
  <p>If I remove first line everything works fine.<br>
  What's wrong? Why this works on Windows and not on Linux?<br>
  Could this be caused from a particular extension?</p>