Experts Round Table Network - SimpleXML: Swap nodes

How can I swap 2 nodes using SimpleXML?

Something like this:

Code

Language: php (GeSHi-highlighted)
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>SimpleXML: How to swap nodes</title>
</head>
<body>
 
<h1>SimpleXML: How to swap nodes</h1>
 
<?
 
$xmlstr = <<<XML
<?xml version='1.0' standalone='yes'?>
<movies>
 <movie>
  <title>PHP: Behind the Parser</title>
  <characters>
   <character>
    <name>Ms. Coder</name>
    <actor>Onlivia Actora</actor>
   </character>
   <character>
    <name>Mr. Coder</name>
    <actor>El Actor</actor>
   </character>
  </characters>
  <plot>
   So, this language. It is like, a programming language. Or is it a
   scripting language? All is revealed in this thrilling horror spoof
   of a documentary.
  </plot>
  <great-lines>
   <line>PHP solves all my web problems</line>
  </great-lines>
  <rating type="thumbs">7</rating>
  <rating type="stars">5</rating>
 </movie>
</movies>
XML;
 
$xml = new SimpleXMLElement($xmlstr);
 
$character0 = $xml->movie[0]->characters[0]->character[0];
$character1 = $xml->movie[0]->characters[0]->character[1];
 
echo "<h2>Character 0</h2><pre>". htmlspecialchars($character0->asXML()) ."</pre>";
echo "<h2>Character 1</h2><pre>". htmlspecialchars($character1->asXML()) ."</pre>";
 
$xml->movie[0]->characters[0]->character[0] = $character1;
$xml->movie[0]->characters[0]->character[1] = $character0;
 
echo "<h2>XML</h2><pre>". htmlspecialchars($xml->asXML()) ."</pre>";
 
?>
 
<p>The content of the character nodes has vanished!</p>
 
</body>
</html>

I found a workaround converting to XML string and using stri_replace... ugly but it works and should be solid.

From the comments on the PHP site, il looks like there is no easy way to insert XML into a simpleXML structure:
http://us2.php.net/simplexml#78855
The technique described in this comment recursively copies the nodes one by one from one structure to the other... Even uglier than my str_replace method IMHO. Looks like this particular code does not copy the XML attributes, but that could be fixed.

Have I missed something? Is there some magic notation that I should use?

Except for that small detail, SimpleXML is great !

Cheers and thanks in advance for your constructive feedback ;)