add-custom-post-order-value-to-post-list-in-wp-admin.php

<?php
/* Display custom post order in the post list */

function jpen_custom_post_order_value( $column, $post_id ){
  if ($column == 'pos' ){
    echo '<p>' . get_post_meta( $post_id, '_custom_post_order', true) . '</p>';
  }
}
add_action( 'manage_posts_custom_column' , 'jpen_custom_post_order_value' , 10 , 2 );
?>