$(document).ready(function() {
    createUsermenuItem("a#usermenu_link_login", "div#usermenu_login", "fileadmin/templates/ajaxtests/ajaxtest_usermenu_login.htm", "");
    createUsermenuItem("a#usermenu_link_register", "div#usermenu_register", "fileadmin/templates/ajaxtests/ajaxtest_usermenu_login.htm", "");
});

function createUsermenuItem(link, div, ajaxurl, ajaxoptions) {
    $(link).click(function() {
        $("div.usermenu_subitem").not(div)
            .slideUp("fast", function() {
                $("a.usermenu_link_selected").not(link).
                    removeClass("usermenu_link_selected");
                if ($(div).html() != "") {
                    showItem(link, div);
                }
                else {
                    $(div).load(ajaxurl, ajaxoptions, function() {
                        showItem(link, div);
                    });
                }
        });
    });
    function showItem(link, div) {
        if ($(div).css("display") == "none") {
            $(link).addClass("usermenu_link_selected");
        }
        $(div).slideToggle("fast", function() {
            if ($(div).css("display") == "none") {
                $(link).removeClass("usermenu_link_selected");
            }
        });
    }
}