Überschrift in Sidebar kann nicht mehr angeklickt werden

<?php 
// Seach the menu hierarchy for the first level page above the 
// currently displayed page.
function get_first_level($page) 
{
    if ($page->post_parent != 0)
        return get_first_level(get_page($page->post_parent));
    else
        return $page->ID;
}
?>


	<div id="sidebar">
	    <?php
	        if (get_the_title() == "Startseite") {
	    ?>
	        <p style="text-align: center;">
	        <img src="<?php bloginfo('stylesheet_directory'); ?>/images/erdkugel.jpg" height="253" width="190" alt="Inspiro" />
	        </p>
	    <?php
            } else {
	    ?>
		<ul>
		    <?php
		    // It may be that there is a wordpressy way to do that, I don't know. 
		    // This removes the link tags from the first level of this menu.
		    $pages = wp_list_pages("title_li=&echo=0&child_of=" . get_first_level($post));
		    $pages = preg_replace("#(<li.+>)<a.+>(\w+)</a>\s*<ul>#U", '$1$2<ul>', $pages);
		    echo $pages;
		    ?>
		</ul>
		<?php
		    }
		?>
	</div>