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;