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";
		anchor.className += " "+"external";
	   	anchor.setAttribute("title","opens in new window");
 		}
 	}
}
window.onload = externalLinks;