[Plugin: Dynamic "To Top" Plugin] Not working corectly with IE9

Hi,
I have the Theme “inove” and when I use your plugin the Submenu-Box will display about 20px deeper. In Crome it looks normal.
The concerning Code is the follow:

<div id="navigation">
	<!-- menus START -->
	<ul id="menus">
		<li class="current_page_item"><a title="Home" href="...">Home</a>
		<li class="page_item page-item-4"><a href="...">Termine</a>
<li class="page_item page-item-6"><a href="...">Ergebnisse</a>
<ul class='children'>
	<li class="page_item page-item-23"><a href="...">Vereinsmeisterschaft</a>
	<li class="page_item page-item-25"><a href="...">Rundenwettk?mpfe</a>
	<li class="page_item page-item-27"><a href="...">Kreismeisterschaft</a>
	<li class="page_item page-item-29"><a href="...">Bezirksmeisterschaft</a>
	<li class="page_item page-item-31"><a href="...">Landesmeisterschaft</a>