jquery use of :last and val()
===

I'm trying to run the code from http://jsfiddle.net/ddole/AC5mP/13/ on my machine and the approach I've use is below or [here][1].

Do you know why that code doesn't work on my machine. Firebug doesn't help me and I can't solve the problem. I think that I need another pair of eyes :(((

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="utf-8">
        <title>jQuery UI Dialog - Modal form</title>
        <link type="text/css" href="css/ui-lightness/jquery-ui-1.8.21.custom.css" rel="stylesheet" />
        <script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>
        <script type="text/javascript" src="js/jquery-ui-1.8.21.custom.min.js"></script>
        <script  type="text/javascript" >
            jQuery(function($) {
                $('.helpDialog').hide();
                $('.helpButton').each(function() {  
                    $.data(this, 'dialog',
                    $(this).next('.helpDialog').dialog({
                        autoOpen: false,  
                        modal: true,  
                        width: 300,  
                        height: 250,
                        buttons: {
                            "Save": function() {
                                alert($('.helpText:last').val());
                                $(this).dialog( "close" );
                            },
                            Cancel: function() {
                                $(this).dialog( "close" );
                            }
                        }
                    })
                );  
                }).click(function() {  
                    $.data(this, 'dialog').dialog('open');  
                    return false;  
                });  
            });  
        </script>
    </head>
    <body>

        <span class="helpButton">Button</span>
        <div class="helpDialog">
            <input type="text" class="helpText" />
        </div>

        <span class="helpButton">Button 2</span>
        <div class="helpDialog">
            <input type="text" class="helpText" />
        </div>

        <span class="helpButton">Button 3</span>
        <div class="helpDialog">
            <input type="text" class="helpText" />
        </div>

        <span class="helpButton">Button 4</span>
        <div class="helpDialog">
            <input type="text" class="helpText" />
        </div>

        <span class="helpButton">Button 5</span>
        <div class="helpDialog">
            <input type="text" class="helpText" />
        </div>    </body>
</html>


  [1]: http://pastebin.com/cADEuzX1