a simple job for any javascript developer

This is a simple job for any javascript developer. I have two webpages that used to have a message pop up when a visitor tried to leave. I recently updated these pages and now this 'exit pop' no longer works. I need the javascript fixed so each page will show the exit pop again. I have: The 2 old pages with a working exit pop, and the 2 new pages where it is not working I need: The 2 NEW pages to have the working exit pop. I will provide: FTP access to the old and new webpages. I do not prepay, but I will fund a milestone for the completed project.