JAccordion problem

JAccordion problem


Hello,
I need a accordion menu based on a defenition list.
Because i have to learn jquery first i try to make one of the demos.
I have now this html file :
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://
www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>jQuery UI Accordion</title>
<link rel="stylesheet" href="demo.css" />
<script type="text/javascript" src="../jquery.accordion.js"></script>
<script type="text/javascript" src="../jquery.accordion.min.js"></
script>
<script type="text/javascript" src="../jquery.accordion.pack.js"></
script>
<script type="text/javascript" src="../lib/jquery.dimensions.js"></
script>
    </head>
<body>
<h1 id="banner"><a href="http://bassistance.de/jquery-plugins/jquery-
plugin-accordion/">jQuery accordion Plugin</a> Demo</h1>
<div id="main">
    <fieldset>
        <legend>Navigation - Unordered List with anchors and nested lists.</
legend>
        

Location-based state-saving: The active element is choosen based
on location.hash: Click one of the links, then reload the page to see
it in action.


        <h3>Code</h3>
        <pre><code class="mix">jQuery('#navigation').accordion({
    active: false,
    header: '.head',
    navigation: true,
    event: 'mouseover',
    fillSpace: true,
    animated: 'easeslide'
});</code></pre>
        <div style="height:250px;margin-bottom:1em;">
            <ul id="navigation">
                <li>
                    <a class="head" href="?p=1.1.1">Guitar</a>
                    <ul>
                        <li><a href="?p=1.1.1.1">Electric</a></li>
                        <li><a href="?p=1.1.1.2">Acoustic</a></li>
                        <li><a href="?p=1.1.1.3">Amps</a></li>
                        <li><a href="?p=1.1.1.4.1">Effects A</a></li>
                        <li><a href="?p=1.1.1.4.2">Effects B</a></li>
                        <li><a href="?p=1.1.1.4.3">Effects C</a></li>
                        <li><a href="?p=1.1.1.4.4">Effects D</a></li>
                        <li><a href="?p=1.1.1.5">Accessories</a></li>
                    </ul>
                </li>
                <li>
                    <a class="head" href="?p=1.1.2">Bass</a>
                    <ul>
                        <li><a href="?p=1.1.2.1">Electric</a></li>
                        <li><a href="?p=1.1.2.2">Acoustic</a></li>
                        <li><a href="?p=1.1.2.3">Amps</a></li>
                        <li><a href="?p=1.1.2.4">Effects</a></li>
                        <li><a href="?p=1.1.2.5">Accessories</a></li>
                    </ul>
                </li>
                <li>
                    <a class="head" href="?p=1.1.3">Drums</a>
                    <ul>
                        <li><a href="?p=1.1.3.2">Acoustic Drums</a></li>
                        <li><a href="?p=1.1.3.3">Electronic Drums</a></li>
                        <li><a href="?p=1.1.3.4">Cymbals</a></li>
                        <li><a href="?p=1.1.3.5">Hardware</a></li>
                        <li><a href="?p=1.1.3.6">Accessories</a></li>
                    </ul>
                </li>
            </ul>
        </div>
    </fieldset>
</body>
</html>
But nothing happens.
What did go wrong ?
Roelof