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";
	}
}