function targetBlank(event) { 
	event = event ? event : window.event; 
	var target = event.srcElement ? event.srcElement : event.target; 
	while (target.nodeName.toLowerCase() != "a" && target.parentNode != null) 
		target = target.parentNode; 
		window.open(target.getAttribute("href"), "_blank"); 

	// DOM 
	if (event.cancelable) event.preventDefault(); 
	// IE 
	return false; 
} 	 
	
function targetBlankBind() { 
	var tags = document.getElementsByTagName("A"); 
	var i; 
	for (i=0; i<tags.length; i++) 
		if (tags[i].getAttribute("rel") == "external") 
			tags[i].onclick = targetBlank; 
} 
			
if (window.attachEvent) { 
	// IE 
	window.attachEvent("onload", targetBlankBind); 
} else { 
	// DOM 
	window.addEventListener("load", targetBlankBind, false); 
}