How to disable automatic logout

I have a laptop that is part of an active directory domain on windows 2003 servers. Our IT security department has implemented group policies that automatically log out a user after 15 minutes of inactivity. Great idea in theory, but bad in practice. On my laptop, I have a need to run video loops that last 30 minutes or more and then repeat, problem is, after 15 minutes my laptop logs out. Is there a way that I can turn this off??