.menu1 {
float:left; width:100%; font-family: "Trebuchet MS",Verdana,Arial,sans-serif; font-size:11px; font-weight: bold;
background:url(../immagini/btn_su.gif) repeat-x top left; 
border-bottom:1px solid #fff; 
}
.menu1 ul {
padding:0;margin:0;list-style-type:none;
}
.menu1 ul li {
float:left; position:relative; background:url(../immagini/divider1.gif) no-repeat top right;
}
.menu1 ul li a, .menu1 ul li a:visited {
width: 139px; text-align: center; float:left; display:block; text-decoration:none;color:#fff; line-height:22px; height:25px; border-bottom:2px solid #fff; border-right:1px solid #83BD5A;
}
.menu1 ul li a.menu1two, .menu1 ul li a.menu1two:visited {
width: 137px; text-align: center; float:left; display:block; text-decoration:none;color:#fff; line-height:22px; height:25px; border-bottom:2px solid #fff; border-right:1px solid #83BD5A;
background-image:url(../immagini/btn_su_prod.gif); background-repeat:repeat-x;}

.menu1 ul li:hover {width:auto;}

.menu1 ul li a:hover {background:url(../immagini/btn_giu.gif) repeat-x top left;}
.menu1 ul li a.menu1two:hover {background:url(../immagini/btn_giu.gif) repeat-x top left;}

.menu1 ul li ul {
display: none;
}
.menu1 table {
margin:0; border-collapse:collapse; font-size:11px; position:absolute; top:0; left:0;
}

/* specific to non IE browsers */
.menu1 ul li:hover ul {
display:block;position:absolute;top:25px;margin-top:1px; left:0;width:140px;border-bottom:1px solid #83BD5A;
}
.menu1 ul li:hover ul.endstop {
left:0;
}
.menu1 ul li:hover ul li ul {
display: none;
}
.menu1 ul li:hover ul li a {
display:block;background:#b1db93;color:#000;height:auto;line-height:15px;padding:4px 16px; width:107px; border:1px solid #83BD5A; border-bottom:0;
}

.menu1 ul li:hover ul li a:hover {
color:#000; background: #83BD5A;
}

.menu1 ul li:hover ul li:hover ul {
display:block; position:absolute; left:141px; top:-1px;
}
.menu1 ul li:hover ul li:hover ul.left {
left:-141px;
}



/* specific to IE5.5 and IE6 browsers */
.menu1 ul li a:hover ul {
display:block;position:absolute;top:25px; t\op:26px; background:#b1db93;left:0; border-bottom:1px solid #83BD5A;
}

.menu1 ul li a:hover ul.endstop {
left: 0;
}
.menu1 ul li a:hover ul li a {
display:block;background:#b1db93;color:#000; height:1px; line-height:15px; padding:4px 16px; width:140px; w\idth:107px; border:1px solid #83BD5A; border-bottom:0;
}

.menu1 ul li a:hover ul li a ul {
visibility:hidden; position:absolute; height:0; width:0;
}
.menu1 ul li a:hover ul li a:hover {
color:#000; background: #83BD5A;
}

.menu1 ul li a:hover ul li a:hover ul {
visibility:visible; position:absolute; top:0;color:#000; left:141px;
}
.menu1 ul li a:hover ul li a:hover ul.left {
left:-141px;
}

<!--[if lte IE 5.5]>
.menu1 ul li a, .menu1 ul li a:visited {height:25px;}