title: tinyMCE textarea in a tinyMCEPopup
body: <p>I created a plugin which opens a tinyMCEPopup.
  In the tinyMCEPopup I have several textareas and need them to be tinyMCE textareas.
  Here is a <em>simplified</em> example of the popup file:</p>
  
  <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"&gt;
  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
  &lt;head&gt;
      &lt;title&gt;&lt;/title&gt;
      &lt;script type="text/javascript" src="../../tiny_mce_popup.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;form action="#" id="multiBoxes"&gt;
      &lt;textarea name="content" id="content" cols="50" rows="15" &gt;&lt;/textarea&gt;
  &lt;/form&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>I tried to init() it or <code>tinyMCE.execCommand('mceAddControl', false, 'content');</code> ... but it does not work!
  Any suggestion?!</p>
  
  <p>Thanks</p>
  
  <p>Marco</p>