Including jQuery UI Sortable in WordPress admin page

[admin]

I'm working on a plugin and encountered a problem where trying to make use of the jQuery UI Sortable. I followed the instruction as in <a href="http://codex.wordpress.org/Function...cripts_Only_on_a_Plugin_Administration_Screen" rel="noreferrer">Codex</a> but issue remained. The jQuery UI sortable does not function and Firebug says

TypeError: jQuery(...).sortable is not a function

.

I'm running on WordPress 3.6 and the code is:

<?php
/*
Plugin Name: Name
Description: Description
Version: 0.1
Author: Bloorchi
*/

add_action( 'admin_menu', 'my_plugin_admin_menu' );

function my_plugin_admin_menu() {
    add_action('admin_print_scripts-' . $page_hook_suffix, 'my_plugin_admin_scripts');
    $page_hook_suffix = add_submenu_page( 'edit.php', 'My Plugin', 'My Plugin', 'manage_options', 'my_plugin-options', 'my_plugin_manage_menu' );
}

function my_plugin_admin_scripts() {
    wp_enqueue_script( 'jquery-ui-sortable' );
}

function my_plugin_manage_menu() {
?>
<table id="test">
    <tbody>
        <tr>
            <td>1</td>
            <td>2</td>
        </tr>
        <tr>
            <td>3</td>
            <td>4</td>
        </tr>
        <tr>
            <td>5</td>
            <td>6</td>
        </tr>  
    <tbody>    
</table>
<script>
    jQuery('table#test tbody').sortable();
</script>
<?php
}