title: adding a namespace when using SimpleXMLElement
body: <p>This is what I am after</p>
  
  <pre><code>&lt;!-- language: lang-xml --&gt;
  &lt;ws:Test&gt;
      &lt;ws:somename2&gt;somevalue2&lt;/ws:somename2&gt;
      &lt;ws:make&gt;
          &lt;ws:model&gt;foo&lt;/ws:model&gt;
          &lt;ws:model&gt;bar&lt;/ws:model&gt;
      &lt;/ws:make&gt;
  &lt;/ws:Test&gt;
  </code></pre>
  
  <p>This is my current code</p>
  
  <pre><code>&lt;!-- language: lang-php --&gt;
  $xmlTest = new SimpleXMLElement('&lt;Test/&gt;', 0, false, 'ws', true);
  $xmlTest-&gt;addChild("ws:somename2", "somevalue2", 'http://microsoft.com/wsdl/types/');
  $make = $xmlTest-&gt;addChild('ws:make', null, 'ws');
  #$make-&gt;addAttribute('name','Ford');
  $make-&gt;addChild('ws:model', 'foo', 'ws');
  $make-&gt;addChild('ws:model', 'bar', 'ws');
  header ("Content-Type:text/xml");
  print_r($xmlTest-&gt;asXML());
  </code></pre>
  
  <p>but it outputs</p>
  
  <pre><code>&lt;!-- language: lang-xml --&gt;
  &lt;Test&gt;
      &lt;ws:somename2&gt;somevalue2&lt;/ws:somename2&gt;
      &lt;ws:make&gt;
          &lt;ws:model&gt;foo&lt;/ws:model&gt;
          &lt;ws:model&gt;bar&lt;/ws:model&gt;
      &lt;/ws:make&gt;
  &lt;/Test&gt;
  </code></pre>
  
  <p>As you can see the ws: is missing from Test </p>