LITHIUM_APP_PATH is already a dir, but doesn't end in /

dirname() strips the last part of the path because
dirname('a/b/c') is 'a/b', regardless of whether c is a directory

config/bootstrap/libraries.php

@@ -59,7 +59,7 @@ define('LITHIUM_APP_PATH', dirname(dirname(__DIR__)));
  * directory as your application.  If you use the same libraries in multiple applications, you can
  * set this to a shared path on your server.
  */
-define('LITHIUM_LIBRARY_PATH', dirname(LITHIUM_APP_PATH) . '/libraries');
+define('LITHIUM_LIBRARY_PATH', LITHIUM_APP_PATH . '/libraries');
 
 /**
  * Locate and load Lithium core library files.  Throws a fatal error if the core can't be found.
@@ -124,4 +124,4 @@ Libraries::add('app', array('default' => true));
 // Libraries::add('li3_docs');
 Libraries::add('li3_flash_message');
 Libraries::add('li3_paginate');
-?>
+?>