droppable in droppable

Question

I have this markup

<ul id="hello" class="cat">
    <ul id="a1" class="cat">
    </ul>
    <ul id="a2" class="cat">
    </ul>
</ul>

I did this thing

$("ul.cat").droppable(
{
    drop:function()
    {
        alert($(this).attr("id"));
    }
});

It always write "hello". only "hello". How can I bind droppable on childs too?

UPD: I want drop in elements in #hello's chidlren AND #hello itself. I want to determine where li was dropped.

Answer 1

I've found the solution: #hello needs greedy:true

http://jqueryui.com/demos/droppable/#propagation