Index: wp-includes/post-template.php
===================================================================
--- wp-includes/post-template.php	(revision 10849)
+++ wp-includes/post-template.php	(working copy)
@@ -383,6 +383,9 @@
 	if ( is_404() )
 		$classes[] = 'error404';
 
+	if ( is_singular() )
+		$classes[] =  $wp_query->post->post_name;
+
 	if ( is_single() ) {
 		the_post();
 
@@ -416,6 +419,8 @@
 		$pageID = $wp_query->post->ID;
 		$page_children = wp_list_pages("child_of=$pageID&echo=0");
 
+		$classes[] = 'pageid-' . $pageID;
+
 		if ( $page_children )
 			$classes[] = 'page-parent';