Conditional Requests (CACHING)

Is it possible to have apache and PHP play nice together with respect to conditional requests? Example: A PHP page sending a Last-Modified header and sets Cache-Control as Must-Validate. So a Cache collects this page. Then someone else requests this page. The cache sends a "Conditional request", asking to have a page sent only if it's newer. PHP/Apache will just send the whole thing again. I would prefer if it didn't. This kind of makes the Last-Modified header useless. Very useless with 'must-validate' set. Oy. Is there a way around this? Ciao! -- Any program which runs right is obsolete. The Doctor What: Guru to the Gods http://docwhat.gerf.org/ docwhat@gerf.org KF6VNC