// this function sets all links that are marked with rel="external" to target="_blank" (standard compliant!)
function externalLinks() {
	if (!document.getElementsByTagName) return;
	var anchors = document.getElementsByTagName("a");
	for (var i=0; i<anchors.length; i++) {
		anchor = anchors[i];
		if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "external") {
			anchor.target = "_blank";
		}
	}
}

window.onload = externalLinks;