[jQuery] How to convert prototype to jquery

[Netto]

My prototype script:

function loginMenu() {
    $('mydiv').innerHTML = "Loading...";
    var param = Form.serialize($('myForm'));
    var myAjax = new Ajax.Updater (
        'myOutputDiv',
        '<%=$app%>/users/login',
        {
                method: 'get',
                parameters: param,
                evalScripts: true
        });
    return false;
}

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