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.title = "Link opens in a new window";
			anchor.target = "_blank";
		}
	}
}
window.onload = externalLinks;