function externalLinks() {  
	 if (!document.getElementsByTagName) return;  
	 var anchors = document.getElementsByTagName("a");  
	 for (var i=0; i<anchors.length; i++) {  
	   var anchor = anchors[i];  
	   if (anchor.getAttribute("href") &&  
	       anchor.getAttribute("rel") == "external")  
	     anchor.target = "_blank";  
	 }  
	}  
	window.onload = externalLinks;