var xOp7Up,xOp6Dn,xIE4Up,xIE4,xIE5,xNN4,xUA=navigator.userAgent.toLowerCase();
if(window.opera){
  var i=xUA.indexOf('opera');
  if(i!=-1){
    var v=parseInt(xUA.charAt(i+6));
    xOp7Up=v>=7;
    xOp6Dn=v<7;
  }
}
else if(navigator.vendor!='KDE' && document.all && xUA.indexOf('msie')!=-1){
  xIE4Up=parseFloat(navigator.appVersion)>=4;
  xIE4=xUA.indexOf('msie 4')!=-1;
  xIE5=xUA.indexOf('msie 5')!=-1;
}
else if(document.layers){xNN4=true;}
xMac=xUA.indexOf('mac')!=-1;

function xGetElementById(e)
{
  if(typeof(e)!='string') return e;
  if(document.getElementById) e=document.getElementById(e);
  else if(document.all) e=document.all[e];
  else e=null;
  return e;
}