function externalLinks() {
	if (!document.getElementsByTagName) {
		return;
	}
	var links = document.getElementsByTagName("a");
	var base = window.location.href;
	var ending = '';
	var m;
	var re = new RegExp("[^/]+$");
	if (base.indexOf("?") != -1) {
		re = new RegExp("[^/]+?.+$");
	}
	m = re.exec(base);

	if (m != null) {
		ending = base.substr(m.index);
	}
	base = base.substr(0, base.length - ending.length);

	for (var i=0; i < links.length; i++) {
		var link = links[i];
		var classes = link.className;
		classes = classes.split(" ");
		if ((link.href && link.href.substr(0,7) == "http://" && link.href.substr(0, base.length) != base) || classes.find('external')) {
			if (!classes.find('internal')) {
				link.target = "_blank";
			}
		}
	}
}
addEvent(window, 'load', externalLinks);