var siSTR='';
if (is_ie) {
    siSTR+='<script language=javascript src="js/menu_ie.js"></script>';
}
else if (is_mac){
    siSTR+='<script language=javascript src="js/menu_mac.js"></script>';
}
else if (is_nav6 || is_moz7) {
    siSTR+='<script language=javascript src="js/menu_ns6.js"></script>';
}
else if (is_nav4up) {
    siSTR+='<script language=javascript src="js/menu_ns4.js"></script>';
}
document.write(siSTR);