function setupExternalLinks() {
	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";
	}
}

if (!listen) {
	alert(
		"relexternal.js was sourced without first loading the utility functions in util.js.\n" + 
		"One such utility function, listen(), is required to use relexternal.js"
	);
} else {
	listen('load', window, setupExternalLinks);
}