function clickBg(e,url_l,url_r) {

  if(url_l=='' && url_r==''){
	  return 0;
  }
  // Calculate viewport dimensions
  var viewportwidth;
  var viewportheight;
  
  // the more standards compliant browsers (mozilla/netscape/opera/IE7) use window.innerWidth and window.innerHeight
  if (typeof window.innerWidth != 'undefined') {
    viewportwidth = window.innerWidth,
    viewportheight = window.innerHeight
  }
  // IE6 in standards compliant mode (i.e. with a valid doctype as the first line in the document)
  else if (typeof document.documentElement != 'undefined'
        && typeof document.documentElement.clientWidth != 'undefined'
        && document.documentElement.clientWidth != 0) {
    viewportwidth = document.documentElement.clientWidth,
    viewportheight = document.documentElement.clientHeight
  }
  // older versions of IE
  else {
    viewportwidth = document.getElementsByTagName('body')[0].clientWidth;
  }
  var IE = document.all?true:false
  if (IE) { // grab the x-y pos.s if browser is IE
    tempX = event.clientX + document.body.scrollLeft
  } else {  // grab the x-y pos.s if browser is NS
    tempX = e.pageX
  }  
  // catch possible negative values in NS4
  if (tempX < 0) { tempX = 0 }
  
  if (tempX < (viewportwidth / 2)) {
    // left
    destination = url_l;
  } else {
    // right
    destination = url_r;
  }
  
  evt = e || window.event;
  if (e.target) targ = e.target;
  else if (e.srcElement) targ = e.srcElement;
  if (targ.nodeType == 3) // Safari bug
    targ = targ.parentNode;
  if (targ.id == 'body') {
    window.open(destination,'_self');
  }
}