I would recommend hanging out on #debian-java (irc.debian.org), and ask for advice there. The people there know their stuff. Is the 3D stuff jogl or something else?
The java bindings for OpenGL, jogl, also have to be packaged for EJS, but the Java 3D is a different package. Regarding jogl and an associated library, I got to get a couple of packages, which is an initial step, but certainly, I will drop to #debian-java to ask help and reviewers.
Indeed, happy hacking, -- Pablo Pita Leira