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;