FX.Slide problem with TinyMCE Textarea

I'm having a problem getting an input TextArea to reappear with FX.Slide.toggle(). I'm using TinyMCE to provide WYSIWYG ability in the TextArea. When the page renders, I see the TextArea correctly. When I toggle its div, it hides fine. But then when I toggle again, it doesn't reappear. Has anyone faced this problem befores? Thanks in advance. Here's the code:

<div id="editText"><textarea id="testa" name="testa" rows="2" cols="50" wrap="off">testing</textarea></div>

<div id="menu_links"><a href="#">Oman3d</a></div>

<script type="text/javascript">
var box = {};
window.addEvent('domready', function(){
box = new MultiBox('mb', {descClassName: 'multiBoxDesc', useOverlay: true});
});

var mySlide = new Fx.Slide('editText');
$('menu').addEvent('click',function(o3dEvent){
o3dEvent = new Event(o3dEvent);
mySlide.toggle();
o3dEvent.stop();
})

</script>

demo?

TinyMCE creates an iframe for it's GUI and just copy the content all the time to the Textarea...
so maybe the iframe just doesn't get's displayed? can't tell without a demo... check with firebug