I've been codeing some stuff in python lately for a program called Noesis.
I'm studying the source code now to write a plugin for it that will export to the j3d format.
Noesis is a free program that also has a viewer built into it and supports many different formats so it's good for alot of different reasons.
You can get it here.........
http://forum.xentax.com/viewtopic.php?f=33&t=4582