document.getElementsByClassName = function(cl) {
var retnode = [];
var myclass = new RegExp('\\b'+cl+'\\b');
var elem = this.getElementsByTagName('*');
for (var i = 0; i < elem.length; i++) {
var classes = elem[i].className;
if (myclass.test(classes)) retnode.push(elem[i]);
}
return retnode;
};

function showhide(j)
{
    var i = 'DownDrop' + j;
    var ic = 'DDlink' + j;
    document.getElementsByClassName("DownDropActive").className = 'DownDrop';
    document.getElementsByClassName("DownDropSub").style.display = 'none';
    
    if (document.getElementById(i).style.display == 'none')
    {
        document.getElementById(i).style.display = '';
        document.getElementById(ic).className = 'DownDropActive';
    }
    return false;
}