[ODE] Rope simulation

[Medvedev Sergey]

Hi everybody.
   I  tried to simulate rope in ODE, seems to br stable when the 
number of nodes up to 10.
I  simulate 3km connection wire, so this rope has 30 nodes  connected 
by ball-joints, the one  end  is unmovable, the rope hangs top-down.
  This construction was not stable when I had tried to give force 
impulse to lowest end.  Have you any idea what causes such problem 
(CFM,ERP may be)
   
  There is also another question: Had anyone tried  to make a rope 
with variable length, when for example you can clew it.