How to Exclude Pages – Mensa Theme

I am trying to exclude a page in the nav menu on my site. I am using the Mensa Theme, and the

<?php wp_list_pages(‘exclude=17,38’ ); ?>

Method is not working. Any ideas?

Here is some code from:

header.php

<!-- BEGIN header -->
	<div id="header">

		<div class="search">
			<form action="<?php echo get_option('home'); ?>/">
				<input type="text" name="s" id="s" value="<?php the_search_query(); ?>" />
				<button type="submit">S</button>
			</form>
		</div>
		<div class="logo">
			<h1><a href="<?php echo get_option('home'); ?>"><?php bloginfo('name'); ?></a></h1>
		</div>

		<ul>
			<li><a href="<?php echo get_option('home'); ?>">Home</a></li>
			<?php dp_list_pages(); ?>
		</ul>

		<div class="break"></div>

	</div>
	<!-- END header -->

functions.php

# Displays a list of pages
function dp_list_pages() {
	global $wpdb;
	$querystr = "SELECT $wpdb->posts.ID, $wpdb->posts.post_title FROM $wpdb->posts WHERE $wpdb->posts.post_status = 'publish' AND $wpdb->posts.post_type = 'page' ORDER BY $wpdb->posts.ID ASC";
	$pageposts = $wpdb->get_results($querystr, OBJECT);
	if ($pageposts) {
		foreach ($pageposts as $post) {
			?><li><a href="<?php echo get_permalink($post->ID); ?>"><?php echo $post->post_title; ?></a></li><?php
		}
	}
}