var nn4                  = document.layers;
var nn6                  = document.documentElement;if(document.all) {nn6 = false;}
var ie4                  = (document.all && !document.getElementById);
var ie5                  = (document.all && document.getElementById);
var mac                  = false; if(navigator.platform.indexOf("Mac") >= 0){mac = true;}

function chgclass(tagname,css) {
  if (!nn4) {
		if (ie4){eval("document.all."+tagname+".className='"+css+"'");}
		else    {eval("document.getElementById('"+tagname+"')"+".className='"+css+"'");}
  }
}