http-stats:
HTTP/1.1 Content-Base header field

The Content-Base field is NOT a standard HTTP header field and may not be supported by all clients.

Common Content-Base header values:

The non-standard "Content-Base" header is only sent by:

NOTE: this header may be sent directly by the server software or from some third party application running on that server.

Sample Content-Base web server response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Content-Length: 5160
Content-Base: http://125.206.203.202/pitney/smartlogin.nsf?Open
Date: Fri, 30 Jul 2010 17:03:47 +0000

<!DOCTYPE html PUBLIC "-//W3C//DTD ...
...
...

Other common HTTP headers

Other less common headers