During the transition of the old Sun websites and downloads to the Oracle websites, the Jumpstart Enterprise Toolkit, aka SUNWjet, aka JET, managed to lose its spot and disappeared from all public servers.
Well, not anymore. You can now download JET again.
Note: it comes with the following statement in the OTN License Agreement which you need to agree to before being able to download:
No Technical Support
Our technical support organization will not provide technical support, phone support, or updates to you for the programs licensed under this agreement.
But if you've used JET before, this won't be new to you.