function evenodd()
{
  var sidebars=document.getElementsByClassName('sidebar','body');
  var widgets;
  for (var j=0;j<sidebars.length;j++){
    widgets=sidebars[j].getElementsByClassName('widget','sidebar');
    for (var i=0;i<widgets.length;i++){
      if(i%2==0)
        widgets[i].className+=' even';
      else
        widgets[i].className+=' odd';
    }
  }
}
function addLoadEvent(func) {
  var old = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      old();
      func();
    }
  }
}
addLoadEvent(evenodd);