Papervision3d remove child memory leak

I have a memory leak problem in papervision - I have a bunch of DAE models loading in Papervision. When I add them I can see the total memory usage for flash (in task manager) go up.

If I then remove models from the scene using

scene.removeChild(model);
model = null;

the memory usage doesn’t go down. I don’t have any references to the model except for the scene.

Does anyone have a working example of loading / unloading models in papervision, where the memory used actually goes down?