Drag behaving strange in IE7

[websam]

Hi there,

I try to make a box drageble and it works in FF and IE6 but in IE7 it
only drags my container, top and bottom and not the content within my
container. The html is like this :

<div id="container">
    <div class="top"><span>Overskrift</span></div>
        ###### This does not get draged in IE7 ######
        <div class="middle-left">
            <div class="middle-right">
                <div class="middle">
                </div>
            </div>
        </div>
        #######################################
    <div class="bottom"><span></span></div>
</div>

The javascript i use is this :

<script type="text/javascript">
    window.addEvent('domready', function() {
        $('container').makeDraggable({
            handle: $$('.top'),
            limit: {'x':[0,3000], 'y':[0,3000]}
        });
    });
</script>

And the css for the middle pert is like this :

div.middle-right
{
    background:url(mr.png) repeat-y right;
    padding:0 13px 0 0;
}

div.middle-left
{
        position:relative;
    display:block;
    background:url(ml-1.png) repeat-y left;
    padding:0 0 0 13px;
}

div.middle
{
    padding:10px 13px 10px 13px;
    background-color:#FFF;
}

I don't know if I do any thing wrong but why woun't it drag the middle
part wish is in my container ?