Fatal error: Call to undefined function short_title() in /www/htdocs/w0065e39/sweetlikes/test/wp-content/themes/twentyten/page2.php on line 38

<div class="hauptnavi">
<ul>
<li>Früchte</li>
<li>Gemüse</li>
...
</ul>
</div>
<div class="subnavi">
<ul>
<li>erbeere(child-categorie von Früchte)</li>
<li>kirsche(child-categorie von Früchte)</li>
...
</ul>
</div>
<div class="sub-subnavi">
<ul>
<li>fruchtfleisch (child-categorie von Erdbeere)</li>
<li>kern (child-categorie von Erdbeere)</li>
...
</ul>
</div>

<div id="main-navigation">

<div class="container">

<ul>
<li<?php if(is_home()){ echo " class=\"current\""; } ?>><a href="<?php bloginfo('url'); ?>/">Home</a></li>
<?php if (!is_page() && !is_home()){ $catsy = get_the_category(); $myCat = $catsy[0]->cat_ID; $currentcategory = '&current_category='.$myCat; }
wp_list_categories('hierarchical=1&depth=1&hide_empty=0&use_desc_for_title=0&orderby=order&title_li='.$currentcategory); ?>
</ul>


</div>
<div class="clear"></div>


</div>

<div id="sub-navigation">
<div class="submenu">
<?php
if(is_category()) {

$breakpoint = 0;
$thiscat = get_term( get_query_var('cat') , 'category' );
$subcategories = get_terms( 'category' , 'parent='.get_query_var('cat') );

if(empty($subcategories) && $thiscat->parent != 0) {
$subcategories = get_terms( 'category' , 'parent='.$thiscat->parent.'' );
}

$items='';
if(!empty($subcategories)) {
foreach($subcategories as $subcat) {
if($thiscat->term_id == $subcat->term_id) $current = ' current-cat'; else $current = '';
$items .= '
<li class="cat-item cat-item-'.$subcat->term_id.$current.'">
<a href="'.get_category_link( $subcat->term_id ).'" title="'.$subcat->description.'">'.$subcat->name.'</a>
</li>';
}
echo "<ul>$items</ul>";
}
unset($subcategories,$subcat,$thiscat,$items);
}
?>



</div>

<div id="sub-sub-navigation">
<div class="sub-submenu">

</div>
</div>