You'll probably be able to do this with JavaScript. If people turn it off in their browsers, screw them! 😃
Okay, so that won't work. Contact the person who does own the php.ini . Maybe he/she will be nice and make the modifications for you. I'm guessing that they might not, since it will take longer for any HTML page to load if PHP has to parse it. Maybe they could force everybody else to change to the .htm file extension?
Okay, I'm being stupid now...that's it for the Merve stupidity take, sorry if I couldn't be of any help.