Edit the wp_page_menu function

Hello,

I have a problem. I entered the function :

<?php wp_page_menu('show_home=1&menu_class=menuitems'); ?>

The function his output is:

<div class="menuitems">
<ul>
<li class="current_page_item"><a href="http://www.pokenonline.nl">Home</a></li>
<li class="page_item page-item-12"><a href="http://www.pokenonline.nl/?page_id=12" title="about">about</a></li>
<li class="page_item page-item-7"><a href="http://www.pokenonline.nl/?page_id=7" title="Contact">Contact</a></li>
<li class="page_item page-item-9"><a href="http://www.pokenonline.nl/?page_id=9" title="fddg">fddg</a></li>
</ul>
</div>

Now, I want the following output, how can i get this:

<div class="menuitems">
			<ul>
				<li><a href="#"><span>Home</span></a></li>
				<li><a href="#"><span>Over Ons</span></a></li>
				<li><a href="#"><span>Diensten</span></a></li>
				<li><a href="#"><span>Portfolio</span></a></li>
				<li><a href="#"><span>FAQ</span></a>	</li>
				<li><a href="#"><span>Blog</span></a>	</li>
				<li><a href="#"><span>Contact</span></a>	</li>
			</ul>
		</div>