Default scenegraph node capabilities?

 
Hello,

I have some code that can take an existing J3D scenegraph and produce a
VRML scene.  This code doesn't work with VisAD (unmodified source)
created scenegraphs because the ALLOW_*_READ capabilities of constituent
nodes aren't set.  I haven't been able to find a method of doing this
w/o modifying the VisAD source.  Is there a reason these capabilities
aren't set by default?  Would it be possible to set the ALLOW_*_READ
capabilities by default or to modify the VisAD API in order allowing one
to specify a different set of default capabilities?

Thanks much,

Tom