code: function () {
  
           var oCalendarTBody = Dom.get(calendarId).tBodies[0],
              aElements = oCalendarTBody.getElementsByTagName("a"),
              oAnchor;
  
           if (aElements.length > 0) {
           
              Dom.batch(aElements, function (element) {
                 if (Dom.hasClass(element.parentNode, "today")) {
                    oAnchor = element;
                 }
              });
              
              if (!oAnchor) {
                 oAnchor = aElements[0];
              }
  
              // Focus the anchor element using a timer since Calendar will try 
              // to set focus to its next button by default
              
              lang.later(0, oAnchor, function () {
                 try {
                    oAnchor.focus();
                 }
                 catch(e) {}
              });
           
           }
           
        }
docs: HACK to keep focus on calendar/overlay so overlay is not hidden when changing page in calendar (inspired by YUI examples)