Index: wp-includes/post.php
===================================================================
--- wp-includes/post.php	(revision 15605)
+++ wp-includes/post.php	(working copy)
@@ -945,6 +945,7 @@
 function get_post_type_labels( $post_type_object ) {
 	$nohier_vs_hier_defaults = array(
 		'name' => array( _x('Posts', 'post type general name'), _x('Pages', 'post type general name') ),
+		'menu_name' => array( _x('Posts', 'post type menu name'), _x('Pages', 'post type menu name') ),
 		'singular_name' => array( _x('Post', 'post type singular name'), _x('Page', 'post type singular name') ),
 		'add_new' => array( _x('Add New', 'post'), _x('Add New', 'page') ),
 		'add_new_item' => array( __('Add New Post'), __('Add New Page') ),
@@ -968,6 +969,11 @@
 
 	if ( isset( $object->label ) && empty( $object->labels['name'] ) )
 		$object->labels['name'] = $object->label;
+	
+	if ( isset( $object->labels ) && empty( $object->labels['menu_name'] ) )
+		$object->labels['menu_name'] = $object->labels['name'];
+	elseif ( isset( $object->label ) && empty( $object->labels['menu_name'] ) )
+		$object->labels['menu_name'] = $object->labels['name'];
 
 	if ( !isset( $object->labels['singular_name'] ) && isset( $object->labels['name'] ) )
 		$object->labels['singular_name'] = $object->labels['name'];
Index: wp-admin/menu.php
===================================================================
--- wp-admin/menu.php	(revision 15605)
+++ wp-admin/menu.php	(working copy)
@@ -122,7 +122,7 @@
 	while ( isset($menu[$ptype_menu_position]) || in_array($ptype_menu_position, $core_menu_positions) )
 		$ptype_menu_position++;
 
-	$menu[$ptype_menu_position] = array( esc_attr( $ptype_obj->labels->name ), $ptype_obj->cap->edit_posts, "edit.php?post_type=$ptype", '', 'menu-top menu-icon-' . $ptype_class, 'menu-posts-' . $ptype_for_id, $menu_icon );
+	$menu[$ptype_menu_position] = array( esc_attr( $ptype_obj->labels->menu_name ), $ptype_obj->cap->edit_posts, "edit.php?post_type=$ptype", '', 'menu-top menu-icon-' . $ptype_class, 'menu-posts-' . $ptype_for_id, $menu_icon );
 	$submenu["edit.php?post_type=$ptype"][5]  = array( $ptype_obj->labels->name, $ptype_obj->cap->edit_posts,  "edit.php?post_type=$ptype");
 	$submenu["edit.php?post_type=$ptype"][10]  = array( $ptype_obj->labels->add_new, $ptype_obj->cap->edit_posts, "post-new.php?post_type=$ptype" );