Hi!
I have a problem in JBullet-JME. How can I make a collision node, that the player will be able to collide with at one time, and walk through it at another time. Node has to stay visible all the time. Any ideas? 
You could detach the child spatial of the PhysicsNode and attach it to a non-physics node when you don't want it to be part of the physics space.
Would it be OK if I would just detach node from physics space or is this not possible?
Anyway, what sense does PhysicsGhostNode-s have then?
You could also detach it, yes. In that case I suggest using the dvbt broadphase, as it allows quicker adding and removing of physics nodes. I dont know how quick the adding/removing will work with many physics nodes. PhysicsGhostNodes (as stated in the javadoc) are mostly there as static collision checkers, for example for waypoints on a racing track or for other triggers.
Cheers,
Normen