Mysterious non-stop reloading after login to a database

After login to an application, the web page reloads non-stop endlessly.

No db design change made has been made in 6 months, and no Domino server update neither.

The behaviour is generic, i.e. it occurs for all web browsers; IE, Firefox, Google Chrome, etc.

Any suggestions would be greatly appreciated.

Subject: ERROR FOUND!

Many, many years ago we set an expiration date for a cookie to “Saturday, 03-Apr-2010” …