Menu FF vs. IE & Opera

#ajaxmenu ul {
	margin: 0;
	padding: 0;
	list-style: none;

	}

#ajaxmenu ul li {
	position: center;
	float: left;
	width:130px;
	display: block;
	text-decoration: none;
	text-align: center;
	font-weight: normal;
}
	
#ajaxmenu ul li ul {
	position: absolute;
	left: 0; /* Set 0px less than menu width */
	top:30px;
	line-height: 38px;

	}
#ajaxmenu ul li a {
	color: #FFFFFF;
	font-weight: bold;
}



/* Styles for Menu Items */
#ajaxmenu ul li.firstcategory {

	color: #062E4B;
	font-weight: bold;
	height: 38px;
	line-height: 38px;
	padding-right: 0px;
	padding-left: 0px;
	background-image: url(http://new.themain.ru/remain/nav-bg-off.jpg);
	background-repeat: repeat;
	background-position: 0px;
	margin: 0px;

	}
#ajaxmenu ul li.category {
	color: #062E4B;
	font-weight: bold;
	height: 38px;
	line-height: 38px;
	padding-right: px;
	padding-left: 0px;
	background-image: url(http://new.themain.ru/remain/nav-bg-off.jpg);
	background-repeat: repeat;
	background-position: -130px;
	margin: 0px;

	}
#ajaxmenu ul li.lastcategory {
	color: #062E4B;
	font-weight: bold;
	height: 38px;
	line-height: 38px;
	padding-right: 0px;
	padding-left: 0px;
	background-image: url(http://new.themain.ru/remain/nav-bg-off.jpg);
	background-repeat: repeat;
	background-position: -222px;
	margin: 0px;

	}


#ajaxmenu ul li.firstcategory:hover, #ajaxmenu ul li.firstcategory.over {
	color: #fff;
	background-image: url(http://new.themain.ru/remain/nav-press.jpg);
}

#ajaxmenu ul li.category:hover, #ajaxmenu ul li.category.over {
	color: #fff;
	background-image: url(http://new.themain.ru/remain/nav-press.jpg);
}
#ajaxmenu ul li.lastcategory:hover, #ajaxmenu ul li.lastcategory.over {
	color: #fff;
	background-image: url(http://new.themain.ru/remain/nav-press.jpg);
}

/* commented backslash \*/ 
* html ul li a {height:1%}
/* end hack */ 
#ajaxmenu li a {
	text-decoration: none;
}

/* hovered lists */
#ajaxmenu li a, #ajaxmenu li.over a {
	color: #fff;
	width: 130px;
	display: block;

}
#ajaxmenu li li a:hover, #ajaxmenu li.over li a:hover {
	background-image: url(images/bullet_11x8_roll.gif)  !important;
	color: #fff;
	background-repeat: no-repeat;
	background-color: #4e4e4e;
	background-position: left center;
	text-indent: 8pt;
}

/* set dropdown */
#ajaxmenu li li a, #ajaxmenu li.over li a {
	color: #ffffff;
	background-image: url(images/bullet_11x8.gif) !important;
	background-repeat: no-repeat !important;
	text-align: left;
	border-right: 0px solid #2f2f2f;
	border-bottom: 0px solid #2f2f2f;
	border-left: 0px solid #2f2f2f;
	font-weight: normal;
	width: 130px;
	background-color: #000000;
	background-position: left center;
	text-indent: 8pt;
}
#ajaxmenu li ul li a {
	background-image: url(images/sub_color_4x25.jpg);
	background-repeat: repeat-x;
	padding-top: 2px;
	padding-bottom: 2px;
	padding-right: 0px;
	padding-left: 0px;
} /* Sub Menu Styles */

#ajaxmenu li ul, #ajaxmenu li.over ul { 
	display: block; 
} /* The pop */
#ajaxmenu {
	margin-right: auto;
	margin-left: auto;
	width: 930px;

}

#myajaxmenu {
	position: absolute;
	top:1px;
	left: 0px;
	display: block;
	z-index: 1000;
}

  <div id="outer">
    <div id="inner">
      <div id="right">
        <div id="right-inner">