I am testing the code from
SOLR-127. I have seen following behaviour for the Expires HTTP header.
HTTP/1.x 200 OK
Expires: Mon, 11 Feb 2008 15:24:49 GMT
Last-Modified: Fri, 29 Feb 2008 14:25:07 GMT
Date: Tue, 04 Mar 2008 08:27:36 GMT
We are going back in time. max-age=2419200 is 4 weeks in seconds. I checked the code and I have not found anything that could trigger that behaviour.