$(document).observe("contentloaded", function() {
    var links = document.body.getElementsBySelector('a');
    links.each(function(anchor) {
        if (anchor.getAttribute("href")) {
            if (anchor.getAttribute("rel") == "new") {
                anchor.target = "_blank";
            }
            else {
                if (anchor.getAttribute("rel") == "self") {
                    anchor.target = "_self";
                }
            }
        }
    });
});