nested sortables creates multiple placeholders in IE

<ul>

<li>menu 1

<ul>

<li>submenu 1<ul></ul></li>

<li>submenu 2<ul></ul></li>

</ul>

</li>

</ul>

if you create sortables from the above <ul>s and connectWith them together, that creates a nested sortable. but, in IE, dragging "submenu 1" (for example) will create two placeholders; 1 for the top <ul> and another for the second-level one.