Index: wp-load.php
===================================================================
--- wp-load.php	(revision 27089)
+++ wp-load.php	(working copy)
@@ -20,9 +20,12 @@
 
 /** Define ABSPATH as this file's directory */
 define( 'ABSPATH', dirname(__FILE__) . '/' );
+define( 'WPINC', 'wp-includes' );
 
 error_reporting( E_CORE_ERROR | E_CORE_WARNING | E_COMPILE_ERROR | E_ERROR | E_WARNING | E_PARSE | E_USER_ERROR | E_USER_WARNING | E_RECOVERABLE_ERROR );
 
+require_once( ABSPATH . WPINC . '/plugin.php' );
+
 if ( file_exists( ABSPATH . 'wp-config.php') ) {
 
 	/** The config file resides in ABSPATH */
Index: wp-settings.php
===================================================================
--- wp-settings.php	(revision 27089)
+++ wp-settings.php	(working copy)
@@ -15,7 +15,8 @@
  *
  * @since 1.0.0
  */
-define( 'WPINC', 'wp-includes' );
+if (!defined( 'WPINC' ))
+    define( 'WPINC', 'wp-includes' );
 
 // Include files required for initialization.
 require( ABSPATH . WPINC . '/load.php' );
@@ -72,7 +73,7 @@
 require( ABSPATH . WPINC . '/functions.php' );
 require( ABSPATH . WPINC . '/class-wp.php' );
 require( ABSPATH . WPINC . '/class-wp-error.php' );
-require( ABSPATH . WPINC . '/plugin.php' );
+require_once( ABSPATH . WPINC . '/plugin.php' );
 require( ABSPATH . WPINC . '/pomo/mo.php' );
 
 // Include the wpdb class and, if present, a db.php database drop-in.