function Tracker(element_object) {
  this.anchors = element_object.getElementsByTagName('A');
  this.domain = new RegExp("^http://[a-zA-Z0-9\._-]*(usyd|sydney).edu.au");
  this.doctypes = new RegExp("\.(pdf|xls|xlsx|doc|docx|ppt|pptx|zip|mov|mp4|mp3|m4v|wmv|wma|jpg|gif|avi|mpg|rar|csv|txt)$");

  this.track = function(anchor_object) {
  
    if(anchor_object.href) {
      
      if (anchor_object.href.match(this.domain) && anchor_object.href.match(this.doctypes) ) {
        
        var docUrl = new String(anchor_object.href.replace(this.domain,""));
        
        if(anchor_object.addEventListener) {
          anchor_object.addEventListener('click', function() { urchinTracker(docUrl); }, false);
        } else {
          anchor_object.onclick = function() { urchinTracker(docUrl); }
        }
        
      }
      
    }
    
  }
  
  for (var x = 0; x < this.anchors.length; x++) {
    this.track(this.anchors.item(x));
  }
}

if(JsHook) {
	JsHook.push("new Tracker(document)");
} else {
	var JsHook = new Array("new Tracker(document)");
}