var url = "http://evain.net/ajax/item.rbx";

function setArticle(id) {
    var opts = { method : "get",
                 parameters : "id=" + id,
                 onComplete : receivedHandler,
                 asynchronous : true };
    var req = new Ajax.Request(url, opts);
}

function receivedHandler(remote) {
    var doc = remote.responseXML.documentElement;
    if (doc) {
        $("author").innerHTML = nodeValue(doc, "author");
        $("article").innerHTML = "<a href=\"" + nodeValue(doc, "link") +
                "\">" + nodeValue(doc, "title") + "</" + "a>";
        $("date").innerHTML = nodeValue(doc, "pubDate");
        $("desc").innerHTML = nodeValue(doc, "description");
    }
}

function nodeValue(node, name) {
    var childs = node.getElementsByTagName(name);
    if (childs.length > 0 && childs.item(0).childNodes.length > 0)
        return childs.item(0).childNodes.item(0).nodeValue;
    return "";
}