document.getElementsByClassName = function(clsTag,clsName) {
    var retVal = new Array();
  
  for (var j = 0; j < clsTag.length; j++) {
    var elements = document.getElementsByTagName(clsTag[j]);
    for (var i = 0; i < elements.length; i++) {
      if (elements[i].className.indexOf(" ") >= 0) {
        var classes = elements[i].className.split(" ");
        for (var j = 0; j < classes.length; j++) {
          if (classes[j] == clsName) retVal.push(elements[i]);
        }
      } else if (elements[i].className == clsName) retVal.push(elements[i]);
    }
  }
    return retVal;
}

function alternate()
{
    if(document.getElementsByTagName)
    {  
    var clsTags = new Array("table","ul");
        var types = document.getElementsByClassName(clsTags, 'alternate');  
        for ( var j=0; j<types.length; j++)
        {
            var rows = types[j].getElementsByTagName("tr");
            for(i = 0; i < rows.length; i++)
            {          
                if(i % 2 == 0)
                {
                    rows[i].className =  addClass(rows[i], 'odd');
                }else {
                    rows[i].className = addClass(rows[i], 'even')
                }
            }
            var lis = types[j].getElementsByTagName("li");  
            for(i = 0; i < lis.length; i++)
            {          
                if(i % 2 == 0)
                {
                    lis[i].className = addClass(lis[i], 'odd');
                }else {
                    lis[i].className = addClass(lis[i], 'even');
                }
            }
        }
    }
}

function addClass(o, classtype){
 var res;
 if(o.className != '')
  res = o.className+' '+classtype;
 else
  res = classtype;
  
 return res;
}