Php domain re-direct question

Hello,
I have question about how to get a specific domain name to point to a specific file. Here’s my issue, I have one main domain (www.something.com) and I have three other promotional type domains that need to point to specific files ([URL=“http://www.something.com/specific-file.php%29”]www.something.com/specific-file.php).

So like, www.promotionaldomain.com pointing to [URL=“http://www.something.com/specific-file.php”]www.something.com/specific-file.php

Is this possible using php? It’s an IIS server and I don’t have access to the admin panel so .htaccess type redirects aren’t possible, any ideas?

thanks!