Index: classes.php
===================================================================
--- classes.php	(revision 6662)
+++ classes.php	(working copy)
@@ -555,6 +555,8 @@
 			$css_class .= ' current_page_item ';
 		elseif ( $_current_page && $page->ID == $_current_page->post_parent )
 			$css_class .= ' current_page_parent';
+			
+		if ( $depth == 1 && $_current_page->post_parent != 0 ) $css_class .= ' current_page_tree';
 
 		$output .= $indent . '<li class="' . $css_class . '"><a href="' . get_page_link($page->ID) . '" title="' . attribute_escape(apply_filters('the_title', $page->post_title)) . '">' . apply_filters('the_title', $page->post_title) . '</a>';