Google Earth is unable to resolve the current relative network links in jug-leaders.kml file. If you prepend the current relative values with "http://www.java.net/kml/", then the file can be loaded into applications like Google Earth with the network links properly resolving to their location on the internet. This will have no impact on the current usage in web applications. Whether fully specified or relatively specified as they are today, they will resolve properly in web applications.
The actual code change will take one minute, but, I gave it an hour estimate to allow for sanity testing of the change and properly committing it in whatever system you are using to manage the sources and deploy changes.