How do i getteh value of an tag and replace

[semon]

Hello
I have a list that lookslike this one:

<div id="menu_cdcats">

<ul class="nav">
<li><a href="?cat=1">START</a></li>
<li><a href="?cat=2">HOME</a></li>

<li class="right"><a href="#"
onClick="javascript:show_menu('menu')">SELECT</a>
   <ul id="menu" class="sub">
   <li><a href="?cat=5"
onClick="javascript:switch_label(this)">SINGLES</a></li>
   ...
   </ul>
</li>

<li><a href="?cat=3">START</a></li>
<li><a href="?cat=4">HOME</a></li>
</ul>

</div>

The function javascript:switch_label(this) is suppose to take tha
value of the <a> tag and replace the value of the parent <li><ul> tag.
i.e.
in the example above, the code should get the value of the <a> tag,
that is "SINGLES", and replace the value in another <a> tag that is
'SELECT'. So SELECT becomes SINGLES

How do i achieve that. I've tied using get and set with no success. I
don't know how to get values of a <tag> inside other tags and so on...


function swith_label(txt) {


}

Thanks