fix problems with gzip compression

darcs-hash:20080122185828-1ec87-37d8149991d56d3b924634598e57ef2d0b6562a8.gz

inc/pageutils.php

@@ -538,6 +538,9 @@ function http_conditionalRequest($timestamp){
 
   // Nothing has changed since their last request - serve a 304 and exit
   header('HTTP/1.0 304 Not Modified');
+
+  // don't produce output, even if compression is on
+  ob_end_clean();
   exit;
 }