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;