Index: wp-admin/includes/class-wp-posts-list-table.php
===================================================================
--- wp-admin/includes/class-wp-posts-list-table.php	(revision 18984)
+++ wp-admin/includes/class-wp-posts-list-table.php	(working copy)
@@ -94,7 +94,7 @@
 
 		$total_items = $this->hierarchical_display ? $wp_query->post_count : $wp_query->found_posts;
 
-		$per_page = $this->get_items_per_page( 'edit_' . $post_type . '_per_page' );
+		$per_page = $this->get_items_per_page( 'edit_' . str_replace( '-', '_', $post_type ) . '_per_page' );
  		$per_page = apply_filters( 'edit_posts_per_page', $per_page, $post_type );
 
 		if ( $this->hierarchical_display )
Index: wp-admin/includes/misc.php
===================================================================
--- wp-admin/includes/misc.php	(revision 18984)
+++ wp-admin/includes/misc.php	(working copy)
@@ -335,7 +335,7 @@
 		$map_option = $option;
 		$type = str_replace('edit_', '', $map_option);
 		$type = str_replace('_per_page', '', $type);
-		if ( in_array($type, get_post_types()) )
+		if ( in_array( $type, str_replace( '-', '_', get_post_types() ) ) )
 			$map_option = 'edit_per_page';
 		if ( in_array( $type, get_taxonomies()) )
 			$map_option = 'edit_tags_per_page';
Index: wp-admin/includes/post.php
===================================================================
--- wp-admin/includes/post.php	(revision 18984)
+++ wp-admin/includes/post.php	(working copy)
@@ -871,7 +871,7 @@
 	elseif ( isset($q['post_status']) && 'pending' == $q['post_status'] )
 		$order = 'ASC';
 
-	$per_page = 'edit_' . $post_type . '_per_page';
+	$per_page = 'edit_' . str_replace( '-', '_', $post_type ) . '_per_page';
 	$posts_per_page = (int) get_user_option( $per_page );
 	if ( empty( $posts_per_page ) || $posts_per_page < 1 )
 		$posts_per_page = 20;