Função Hover não funciona no IE

Olá...

Criei um efeito hover que ao passar o mouse abre os submenus... mais o problema é que não funciona no IE.. alguem pode me ajudar!

#menu {
 background: -moz-linear-gradient(top, rgba(255,255,255,1) 0%, rgba(255,255,255,0) 100%);
 background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(255,255,255,1)), color-stop(100%,rgba(255,255,255,0)));
 margin:0px; height:0px; line-height:31px; padding-top:15px; font-size:13px; color:#000; text-shadow:0 0 2px #fff; text-decoration:none; text-align:center;
 position:absolute; right:0; top:40px; width:770px; list-style: none;}
}

#menu ul {

 float: left;
 list-style-type: none;
 width: 100%;
}

#menu ul li {

 border-radius: 3px;
 float: left;
 font-size:13px;
 padding-top: 15px;
 position: relative;
 list-style: none
}

#menu ul li:hover{

 background: -moz-linear-gradient(top, rgba(255,255,255,1) 0%, rgba(255,255,255,0) 100%);
}

#menu ul li:hover ul{

	left:0;
}

#menu ul li a {

 display:block;
 font-weight: bold;
 text-decoration: none;
}

#menu ul li ul {

 position:absolute;
 left:-999em;
 width:200px;
 border-top:none;
}

#menu ul li ul li{

 width:98px;
	top: -10px;
 background:-ms-linear-gradient(top, rgba(255,255,255,1) 0%,rgba(255,255,255,0) 100%); background: linear-gradient(to bottom, rgba(255,255,255,1) 0%,rgba(255,255,255,0) 100%);
 background: -webkit-gradient(linear, left top, left bottom,);
 border-bottom:1px solid #ebebeb;
}

#menu ul li ul li ul{

	display:none;
	position:absolute;
	left:220px;
	top:0px;
 background:-ms-linear-gradient(top, rgba(255,255,255,1) 0%,rgba(255,255,255,0) 100%); background: linear-gradient(to bottom, rgba(255,255,255,1) 0%,rgba(255,255,255,0) 100%);
 background: -webkit-gradient(linear, left top, left bottom,);

}

#menu ul li ul li:hover ul{

	display:block;
	position:absolute;
	left:100px;
	top:10px;
	width:290px;
}

#menu span { display:block; height:37px; margin:2px auto; background:url(http://ohmsapoio.com.br/2.0/sistema/img/icons/topsession.png) }
#menu .empresa span { width:38px; background-position:-788px 0 }
#menu .infra span { width:35px; background-position:-983px 0 }
#menu .politica span { width:45px; background-position:-1019px 0 }
#menu .pagamento span { width:49px; background-position:-109px 0 }
#menu .cases span { width:47px; background-position:-1227px 0 }
#menu .users1 span { width:47px; background-position:-2059px 0 }
#menu .users2 span { width:47px; background-position:-1812px 0 }
#menu .submenu .subusuario ul { width:47px; background-position:-1812px 0 }
#menu .empresa a.selected span, #top_session .empresa a:hover span { background-position:-788px -37px }
#menu .infra a.selected span, #top_session .infra a:hover span { background-position:-983px -37px }
#menu .politica a.selected span, #top_session .politica a:hover span { background-position:-1019px -37px }
#menu .pagamento a.selected span, #top_session .pagamento a:hover span { background-position:-109px -37px }
#menu .cases a.selected span, #top_session .cases a:hover span { background-position:-1227px -37px }
#menu .users1 a.selected span, #top_session .users1 a:hover span { background-position:-2059px -37px }
#menu .users2 a.selected span, #top_session .users2 a:hover span { background-position:-1812px -37px }
}