Index: wp-includes/post.php
===================================================================
--- wp-includes/post.php	(revision 17644)
+++ wp-includes/post.php	(working copy)
@@ -910,7 +910,7 @@
 		'permalink_epmask' => EP_PERMALINK, 'can_export' => true, 'show_in_nav_menus' => null, 'show_in_menu' => null,
 	);
 	$args = wp_parse_args($args, $defaults);
-	$args = (object) $args;
+	$args = (object) apply_filters( 'pre_register_post_type', $args, $post_type );
 
 	$post_type = sanitize_key($post_type);
 	$args->name = $post_type;
@@ -1017,7 +1017,7 @@
 		register_taxonomy_for_object_type( $taxonomy, $post_type );
 	}
 
-	return $args;
+	return apply_filters( 'register_post_type', $args, $post_type );
 }
 
 /**