Unknown or expired link?
bayareaguy: This problem stems from a limitation of the way HN maintains state.  An earlier post with some links to the problem code is here: http://news.ycombinator.com/item?id=163755This is a well known problem pg hasn't gotten around to fixing.  See YC: "unknown or expired link" -- fix it already
(790 days ago)
http://news.ycombinator.com/item?id=28944