Unregistering a product from the Sun Connection requires user authentication which is a bad user experience. We will not want to prompt the user to login for unregistration and thus we don't unregister the JDK when it is uninstalled.

The downside of this is that when a user upgrades to a new version of JDK, the previously registered JDKs will still show up in the Inventory Channel and also the service tag registry if exists on the system but these JDKs no longer exist.

This feature is very similar to the JDK registration preference feature (6676377) and this depends on the Sun Connection group to provide a solution to unregister a registered JDK without requiring user authentication.