Duplicating/Cloning Multiple Form Fields

Question

Instead of looking for a plugin I found a piece of code that solves my problem, unfortunately because I am not using a plugin this post doesn’t relate to WordPress and is off-topic. For those of you who are curious the code I am using is at:
http://charlie.griefer.com/blog/2009/09/17/jquery-dynamically-adding-form-elements/

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <title></title>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js"></script>

    <script type="text/javascript">
        $(document).ready(function() {
            $('#btnAdd').click(function() {
                var num     = $('.clonedInput').length;
                var newNum  = new Number(num + 1);

                var newElem = $('#input' + num).clone().attr('id', 'input' + newNum);

                newElem.children(':first').attr('id', 'name' + newNum).attr('name', 'name' + newNum);
                $('#input' + num).after(newElem);
                $('#btnDel').attr('disabled','');

            if (newNum == 5)
                $('#btnAdd').attr('disabled','disabled');
        });

        $('#btnDel').click(function() {
            var num = $('.clonedInput').length;

            $('#input' + num).remove();
            $('#btnAdd').attr('disabled','');

            if (num-1 == 1)
                $('#btnDel').attr('disabled','disabled');
        });

        $('#btnDel').attr('disabled','disabled');
    });
    </script>
</head>

    <body>
        <form id="myForm">
            <div id="input1" class="clonedInput">
                Name: <input type="text" name="name1" id="name1" />
            </div>

            <div>
                <input type="button" id="btnAdd" value="add another name" />
                <input type="button" id="btnDel" value="remove name" />
            </div>
        </form>
    </body>
</html>