This sounds like a question for the phpbb guys.  And by the way, Apache2+PHP is still very much experimental.  I would suggest going back to Apache 1.3.

phpBB has seen this issue, but points the finger back at php instead. It looks like ie caches the php files in temporary internet files. Setting your temp int files to only cache 1MB is the only work around I have found so far.
I found a bit of code that forces the browser not to cache the php files, but I have yet to get it to work.

header("Cache-Control: post-check=0, pre-check=0", false);
header("Pragma: no-cache"); 
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
/* Date in the past*/

header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); 
/* always modified*/

header("Cache-Control: no-cache, no-store, must-revalidate");
/* HTTP/1.1 */read

Anywho, here is the snip from phpBB.


----- Posted by adrien at 8:27 AM on 11-26-2002 ----- 


when "refreshing" a page css gets printed on page using ie. i thought this was a problem with my site only, but also phpbb.com is experiencing it!! 


 
----- Posted by psoTFX at 7:43 AM on 11-27-2002 ----- 


This happens randomly for most, we've never been able to track down where the problem may be coming from ... some have suggested it's the browser, others the server, others phpBB ... given it's lack of repeatability I'm afraid there isn't much we can do. It may be another bug is causing this and thus fixing it will solve the problem ... otherwise ... we welcome information on how to replicate the problem consistently 


 
----- Posted by adrien at 12:37 AM on 12-20-2002 ----- 


Not sure if this helps, but this problem occours to me even when using the back button in phpmyadmin 2.3.0 and only when using IE, opera, mozilla and netscape seem immune to this on win2k.

hope this helps
adrien 


 
----- Posted by psoTFX at 5:29 AM on 12-20-2002 ----- 


This would therefore seem to indicate it's a "browser" problem given it's existence on something other than phpBB. 


 
----- Posted by adrien at 5:32 AM on 12-20-2002 ----- 


yes, my thoughts as well

I know some people with whom it does work with the same configuration as me and even with internet explorer, so there must be something that makes it work, I have been back and forth with the configuration files and can not notice anything. I'm afraid i've had to go with IIS (I'm Ashamed) as apache 1.3 dosen't have certain features I need. If any1 finds anything let me know