Send a stop command to JWplayer playing in a pop-up php window when the window is closed - repost

We have a Magento website which uses downloadable products (mainly image and videos). The videos displayed in the Product Search/Catalog page have an option to preview the video. This is a simple button which fires a Javascript function to open a new popup window containing a php page. This php page has code to call the JWPlayer video player and play the video. However if the new window is closed the video keeps on playing. We need to stop this when the window is closed. According to the JWPlayer documentation on [login to view URL] we need to send a stop command to the player when it is closed. I need someone who can acomplish this fairly quickly and can start within 24 hours. I expect this is a very simple job for someone who is an expert in PHP and javascript. If you know your way around Magento too, that is likely to help, but I can give you guidance on the files that are currently used to open and play the videos. If you want to see it in action please take a look at [login to view URL] and click the 'View Video' button under the images (Left most button).