auto appending .php extension

Hi Folks, I'm using PHP 4.3.10, the Zend Optimizer and Apache 1.3.33. Somehow, if I want to open for example /dikkerapper.php, it is also possible to access it through /dikkerapper (without the .php extension) I haven't seen this before, but when I checked it also occurs on my other servers. The thing is, it causes some big problems with mod_rewrite. For example: the contents of the dir: /dikkerapper.php /dispatcher.php And the mod_rewrite directives are set like this: /hello -> /dispatcher.php?a=hello /how/are/you -> /dispatcher.php?a=how/are/you but when /dikkerapper is requested, it first (apperently) finds dikkerapper.php is found in the directory, and the url is rewritten to: /dispatcher.php?a=dikkerapper.php This might be an apache issue, but can also be related to php.ini I guess. Any ideas? I don't get any replies on the apache configuration newsgroups. I'm using slackware packages for php and apache. regards, Evert