html code in pre tags problem

I insert this in the editor:

<pre>
&lt;div id="carosello"&gt;
  &lt;div class="scroller"&gt;
    &lt;div class="content"&gt;</pre>

Save the text in the database, all is ok.
But when I re-open the text in the editor, become:

<pre></pre>
<div id="carosello">
   <pre>  </pre>
   <div class="scroller">
      <pre>    </pre>
      <div class="content">

oh no!! must preserve the entity and not rebuild tags.
when javascript is disabled, the text is correct in textarea.