Caching problems .. I think

Hi guys I have a rather simple setup: A few forms chained after each other (the first leds to the second which leeds to the third and so on) I´m using sessions - and starting each page like this: header('Expires: ' . gmdate('D, d M Y H:i:s', (time() + (60 * 10))) . ' GMT'); session_cache_limiter('private_no_expire'); session_start(); ... which I believe gives each page (and form result) a caching time of 10 minutes. The problem is that when using the back button in IE - IE complains about the page and tells med that this page is the result of a form and that the content has been blocked. Can anyone tell me how to awoid this problem, so the backbutton can be used, and stil give each page a caching time of 10 minutes? -- Regards Søren Schimkat www.schimkat.dk