javascript firstChild

poradte prosim co delam blbe...

tenhle kod mi v alertu hodi text Undefined:


<ul id="pokus">
<li id="li_1">AHOJ</li>
<li id="li_2"><div id='status' class="notice">Text Text</div></li>
<li id="li_3">AHOJ</li>
<li id="li_4">AHOJ</li>
<li id="li_5">AHOJ</li>
</ul>


<script type="text/javascript">
//<![CDATA[

var el = document.getElementById('pokus').firstChild;


alert(el.innerHTML);


//]]>
</script>