Index: wp-includes/class-wp-xmlrpc-server.php
===================================================================
--- wp-includes/class-wp-xmlrpc-server.php	(revision 40721)
+++ wp-includes/class-wp-xmlrpc-server.php	(working copy)
@@ -1322,6 +1322,8 @@
 			'sticky'         => null,
 			'enclosure'      => null,
 			'ID'             => null,
+			'menu_order'     => null,
+			'to_ping'        => null,
 		);
 
 		$post_data = wp_parse_args( array_intersect_key( $content_struct, $defaults ), $defaults );