[vtkusers] crash when deleting point from PolyData

[jelle]

Hi,

I'm using the python bindings with tvtk to write a simple program for which i
need to interact with a set of points. Right now, I'm trying to write the
functions that deal with the interaction. To get an understanding of those I
made a script where I use PointSource to get a spherical set of points, from
which one is selected with PointPicker, which than is deleted. I've made sure
that the object from which I will delete the point and the ID returned by
PointPicker refer to the same object.
Though when I call PointSource.GetOuput().DeletePoint(ptID), VTK crashes.
I've experimented with calling BuildLink & BuildCells, but it still behaves the
same. 

So, is it nessecary to call PointSource.BuildLinks, or perhaps
PointSource.BuildCells, before being able to delete one of its points?

What am I doing wrong here?

Many thanks,

-jelle