[ODE] composite object split

[Guillaume Jouffroy]

I have changed my composite object method construction. Now I use the 
geomOffset method, to position all geoms of my object. What I do is 
actually position one geom at the needed place and use offset to 
position the other geoms. All are set to the same body.
Now my composite object lies on the ground (in one piece !!) but ... it 
start dancing :-/

Could you please give me any clue of the reasons that may produce this 
strange behavior ?