Deploying binary PHP extensions

Hi, I have recently started developing a product (closed source) in PHP and need to implement portions of it as an extension, primarily for performance reasons. I would therefore like to deliver this extension in binary form as part of the product. Although I have never developed PHP extensions before I have started, and have got a simple one working. I can run it from the command line (php -f testscript.php) without any problems, but can not get it to work when I try to install it under the web server on another machine. I have copied over the .so file and placed it in the modules directory, and I have added an entry to the php.ini file for my new extension. (ALL php.inifiles I could find actually...). When I try to run it there using a couple of test scripts, it does not work. It does not seem to be able to execute the extension, and I can not see the extension or the extension parameters when I run php_info(). I suspect there are one or more steps I must have missed somewhere. Can someone give me a pointer in the right direction? Do I need to recompile or reconfigure PHP on the server? How would I do this? What is the best way to deploy extensions in binary form to a customer?