function subNavRollOvers(){
    var navigation = document.getElementById('nav');
    var navItem = navigation.getElementsByTagName('li');
    
    for(i=0; i<navItem.length; i++){
        navItem[i].onmouseover = function (){rollOver(this, true)}
        navItem[i].onmouseout = function (){rollOver(this, false)}
    }
    
    function rollOver(currentItem, bool){
        var activeLink = currentItem.getElementsByTagName("a");
        var subNavigation = currentItem.getElementsByTagName("div");
        
        for(x=0; x<activeLink.length; x++){
            if(bool){
                activeLink[x].className = "on";
            }else{
                activeLink[x].className = "";
            }
        }
        
        for(y=0; y<subNavigation.length; y++){
            if(bool){
                subNavigation[y].className = "roll-over-menu show";
            }else{
                subNavigation[y].className = "roll-over-menu hide";
            }
        }
    }
}