--- menu_block.module.orig	2009-06-23 11:05:35.000000000 +0200
+++ menu_block.module	2009-06-23 12:13:46.000000000 +0200
@@ -60,6 +60,9 @@
       'template' => 'menu-block-wrapper',
       'arguments' => array('content' => NULL, 'settings' => NULL),
     ),
+    'menu_block_menu' => array(
+      /** @TODO */
+    ),
   );
 }
 
@@ -442,8 +445,17 @@
     }
   }
 
+  $output = theme('menu_block_menu', $items);
+
+  return $output ? theme('menu_tree', $output) : '';
+}
+
+function theme_menu_block_menu($items) {
+  $output = '';
+
   $num_items = count($items);
   $i = 1;
+
   foreach (array_keys($items) as $key) {
     // Render the link.
     $link_class = array();
@@ -457,6 +469,7 @@
       $items[$key]['link']['localized_options']['attributes']['class'] = implode(' ', $link_class);
     }
     $link = theme('menu_item_link', $items[$key]['link']);
+
     // Render the menu item.
     $extra_class = array();
     if ($i == 1) {
@@ -465,6 +478,7 @@
     if ($i == $num_items) {
       $extra_class[] = 'last';
     }
+    $extra_class[] = 'child-'.$i;
     $extra_class[] = 'menu-mlid-' . $items[$key]['link']['mlid'];
     if (!empty($items[$key]['link']['leaf_has_children'])) {
       $extra_class[] = 'has-children';
@@ -474,7 +488,9 @@
     }
     $extra_class = !empty($extra_class) ? implode(' ', $extra_class) : NULL;
     $output .= theme('menu_item', $link, $items[$key]['link']['has_children'], $items[$key]['below'], $items[$key]['link']['in_active_trail'], $extra_class);
+
     $i++;
   }
-  return $output ? theme('menu_tree', $output) : '';
+
+  return $output;
 }