IE 8 dropdown menu not working for Inove theme

I modified (heavily) the Inove theme for the website I’m working on, and I seem to have broken something that made the dropdown menus work in IE. I’m testing in IE 8, since that’s the only version I have.

The preview of Inove in extend/themes/inove does work in IE, so I must have done something significant to my version. Perhaps I’m an idiot and am not looking in the right places, but that’s why I’m asking you.

I ran my CSS through a file comparer to check it against the original version, and I just don’t see anything that I changed that should affect it at all.

The site is at horizonsrhigh.org/wordpress.

My first question would be, “Where is the code that makes the Inove dropdowns work? I can’t seem to find it in the CSS.” My second is, “What bits of the code do you want me to post for you to examine?” I will post here the bits that seem to apply to the dropdowns.

(Apologize for the length.) I don’t seem to have any idea what part of it applies, so here’s the navigation section of my modified code.

/* navigation START */

#navigation {

	background: url(img/ndes/nav_bar.png) center top no-repeat;

	border-bottom:1px solid #A6A6A6;

	margin-left:-12px;

	margin-right:-12px;

	padding-left:12px;

	padding-right:12px;

}

#menus li {

	display:inline;

	list-style:none;

}

#menus li a {

	background:transparent url(img/ndes/nav_bg.png) center no-repeat;

	display:block;

        color:#FFF;

	height:44px;

	line-height:36px;

	padding:0 20px;

	margin-left:-10px;

	text-decoration:none;

	font-size:14px;

	float:left;

	z-index:1;

}

#menus li a:hover, 

#menus li a.current {

	background-position:50% -44px;

}

#menus li.current_page_item a, 

#menus li.current-cat a {

	background-position:50% -88px;

}

#menus li.current_page_item a:hover, 

#menus li.current-cat a:hover,

#menus li.current_page_ancestor a:hover {

	background-position:50% -132px;

}

#menus li.current_page_ancestor a {

	background-position:50% -88px;

}

#menus li a.home {

        background: url(img/ndes/nav_home.gif) no-repeat;

	background-position:50% -1px;

	width:45px;

	padding:0;

	margin-left:0;

	text-indent:-999em;

}

#menus li a.home:hover {

	background-position:50% -45px;

}

#menus li.current_page_item a.home {

	background-position:50% -1px;

}

#menus li a.lastmenu:hover {

	background-position:0 0;

	cursor:default;

}

#searchholder {

	background: url(img/ndes/nav_search.gif) left bottom no-repeat;

	float:right;

/*	height:138px;  */

	width:300px;

	margin:0px;

	padding: 102px 0px 5px 28px;

}

#searchbox {

	background: url(img/searchbox.gif) no-repeat;

	width:209px;

	height:21px;

	display:block;

	float:left;

	margin-top:4px;

	margin-right:10px !important;

	margin-right:5px;

	padding:3px 2px;

}

#searchbox .textfield {

	background:none;

	border:0px;

	width:185px;

	float:left;

	margin-right:2px;

	padding-left:2px;

}

#searchbox .button {

	background:none;

	border:0px;

	width:18px;

	height:18px;

	cursor:pointer;

	float:left;

	margin-top:1px;

}

#searchbox .searchtip {

	color:#999;

}

/* navigation END */
/* submenu START */
(Didn't change anything in here.)
/* submenu END */

Any other comments/criticisms/improvements/”YOU SUCK”s about the website will be gratefully received/considered/thankfully accepted/returned with a baseball bat to the face. (I’m !serious about the baseball bat, any of you who are airport baggage checkers. Else, serious.)