Absolute rather than relative times in expires directives

[Mark James]

Hi,

I have a static HTML page that is updated at midnight each day. So I'd like to set its expires directive to an absolute 
rather than a relative time.

I was thinking of something like

    expires at <crontab-line>

e.g. expires at 0 0 * * *

My questions:

   - Is there an existing solution?
   - If not, is anyone working, or planning to work, on one?
   - If not, would I have to write a core patch, or could it be done in an extension?
   - If a core patch, is there a good chance it would be accepted?
   - Can anyone suggest a better way than the above?

Perhaps I should just rely on mtime etags (http://github.com/mikewest/nginx-static-etags), and handle the extra requests 
and 304 responses.

Mark