diff --git a/wp-admin/admin-ajax.php b/wp-admin/admin-ajax.php
index ad2fdae669..19e89ff593 100644
--- a/wp-admin/admin-ajax.php
+++ b/wp-admin/admin-ajax.php
@@ -34,7 +34,10 @@ send_nosniff_header();
 
 do_action( 'admin_init' );
 
-$core_actions_get = array( 'fetch-list', 'ajax-tag-search', 'wp-compression-test', 'imgedit-preview', 'oembed-cache', 'autocomplete-user' );
+$core_actions_get = array(
+	'fetch-list', 'ajax-tag-search', 'wp-compression-test', 'imgedit-preview', 'oembed-cache',
+	'autocomplete-user', 'dashboard-widgets',
+);
 
 $core_actions_post = array(
 	'oembed-cache', 'image-editor', 'delete-comment', 'delete-tag', 'delete-link',
diff --git a/wp-admin/includes/ajax-actions.php b/wp-admin/includes/ajax-actions.php
index be77857844..9651e85d20 100644
--- a/wp-admin/includes/ajax-actions.php
+++ b/wp-admin/includes/ajax-actions.php
@@ -186,6 +186,26 @@ function wp_ajax_autocomplete_user() {
 	wp_die( json_encode( $return ) );
 }
 
+function wp_ajax_dashboard_widgets() {
+	require ABSPATH . 'wp-admin/includes/dashboard.php';
+
+	switch ( $_GET['widget'] ) {
+		case 'dashboard_incoming_links' :
+			wp_dashboard_incoming_links();
+			break;
+		case 'dashboard_primary' :
+			wp_dashboard_primary();
+			break;
+		case 'dashboard_secondary' :
+			wp_dashboard_secondary();
+			break;
+		case 'dashboard_plugins' :
+			wp_dashboard_plugins();
+			break;
+	}
+	wp_die();
+}
+
 /*
  * Ajax helper.
  */
diff --git a/wp-admin/includes/update-core.php b/wp-admin/includes/update-core.php
index 2b62afb515..653c11261a 100644
--- a/wp-admin/includes/update-core.php
+++ b/wp-admin/includes/update-core.php
@@ -327,6 +327,9 @@ $_old_files = array(
 'wp-includes/js/tinymce/themes/advanced/skins/wp_theme/img/separator.gif',
 // 3.4
 'wp-admin/images/logo-login.png',
+'wp-admin/index-extra.php',
+'wp-admin/network/index-extra.php',
+'wp-admin/user/index-extra.php',
 );
 
 /**
diff --git a/wp-admin/index-extra.php b/wp-admin/index-extra.php
deleted file mode 100644
index d78bada1f6..0000000000
--- a/wp-admin/index-extra.php
+++ /dev/null
@@ -1,38 +0,0 @@
-<?php
-/**
- * Handle default dashboard widgets options AJAX.
- *
- * @package WordPress
- * @subpackage Administration
- */
-
-define('DOING_AJAX', true);
-
-/** Load WordPress Bootstrap */
-require_once( './admin.php' );
-
-/** Load WordPress Administration Dashboard API */
-require(ABSPATH . 'wp-admin/includes/dashboard.php' );
-
-@header( 'Content-Type: ' . get_option( 'html_type' ) . '; charset=' . get_option( 'blog_charset' ) );
-send_nosniff_header();
-
-switch ( $_GET['jax'] ) {
-
-case 'dashboard_incoming_links' :
-	wp_dashboard_incoming_links();
-	break;
-
-case 'dashboard_primary' :
-	wp_dashboard_primary();
-	break;
-
-case 'dashboard_secondary' :
-	wp_dashboard_secondary();
-	break;
-
-case 'dashboard_plugins' :
-	wp_dashboard_plugins();
-	break;
-
-}
diff --git a/wp-admin/js/dashboard.dev.js b/wp-admin/js/dashboard.dev.js
index ed0f862097..6709ba7bde 100644
--- a/wp-admin/js/dashboard.dev.js
+++ b/wp-admin/js/dashboard.dev.js
@@ -41,7 +41,7 @@ jQuery(document).ready( function($) {
 			if ( e.length ) {
 				p = e.parent();
 				setTimeout( function(){
-					p.load( ajaxurl.replace( '/admin-ajax.php', '' ) + '/index-extra.php?jax=' + id, '', function() {
+					p.load( ajaxurl + '?action=dashboard-widgets&widget=' + id, '', function() {
 						p.hide().slideDown('normal', function(){
 							$(this).css('display', '');
 						});
diff --git a/wp-admin/network/index-extra.php b/wp-admin/network/index-extra.php
deleted file mode 100644
index 17ead78684..0000000000
--- a/wp-admin/network/index-extra.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-/**
- * Handle default network dashboard widgets options AJAX.
- *
- * @package WordPress
- * @subpackage Multisite
- * @since 3.1.0
- */
-
-/** Load WordPress Administration Bootstrap */
-require_once( './admin.php' );
-
-require( '../index-extra.php' );
diff --git a/wp-admin/user/index-extra.php b/wp-admin/user/index-extra.php
deleted file mode 100644
index 4881263501..0000000000
--- a/wp-admin/user/index-extra.php
+++ /dev/null
@@ -1,12 +0,0 @@
-<?php
-/**
- * Handle default dashboard widgets options AJAX.
- *
- * @package WordPress
- * @subpackage Administration
- * @since 3.1.0
- */
-
-require_once( './admin.php' );
-
-require( '../index-extra.php' );