[ODE] using ode with python

[k]

Hi,

i want to use ODE and plib with python.
So i build wrappers for both using swig and
implement a little example, like test_boxstack.

But now ODE does crazy things. The box goes up and
down and does not stay. After a while i get a segmentation
fault.
Another crazy thing is that the z-Position dGeomGetPosition() gives back
is around 0.3. 

I used the same settings like in test_boxstack and played
a lot with all settings to get the simulation stable.

I located the segmentation fault in transfer_i_to_C().

I'm new with ODE and now a bit helpless.
So i can't describe the problem exactly - sorry for that.

In http://q12.org/pipermail/ode/2001-December/000692.html
a similar (and fixed) problem is described.  
Does anybody have any suggestion for a solution or similar
experiences? 

thanks
kristian