2012-08-31-menu_block-default-fallback.patch

diff --git a/menu_block.module b/menu_block.module
index 3925cdd..486da40 100644
--- a/menu_block.module
+++ b/menu_block.module
@@ -275,6 +275,11 @@ function menu_tree_build($config) {
     if (!empty($patterns[$config['menu_name']])) {
       $config['menu_name'] = $patterns[$config['menu_name']];
     }
+    // If no match was found, fall back to the first candidate.
+    // This is a changed behavior form the standard behavior of menu_block.
+    else {
+      $config['menu_name'] = array_shift(array_keys($menu_order));
+    }
     $config['parent_mlid'] = 0;

     // If no menu link was found, don't display the block.