var hoverclassname = " dropdownover"

function over(name) {
   var el = document.getElementById(name);
   if (el.className.indexOf(hoverclassname) == -1) el.className += hoverclassname;
}

function out(name) {
   var el = document.getElementById(name);			   
   el.className = el.className.replace(hoverclassname,"");
}