[vtkusers] vtkImagePlaneWidget crashes after a second load of data

[Flo]

Dear all:

I use vtkImagePlaneWidget in my application with the original code.
Using it while loading a dataset is fine.
However, while, in the same application sequence, I re-load a second  
set of data, as soon as I click or interact with any of the plane I  
have a crash. However, interacting with the renderer (outside the  
ImagePlane outline but inside the renderwindow, meaning zooming and  
rotation) is fine.

Any idea where this kind of crash my come from ?

regards,
Flo.