I receieve an email from a person concerned with the engine and the play ground. Here is the text of teh email
The moterized beam gives the other beam too much velocity. The bug is highly
reproducible. Just run the attached file.
and here is the file.
<?xml version="1.0" encoding="ISO-8859-1"?>
<root xmlns="root"><fileinfo ID="NewtonPlayGround (2004-2006 by Sascha Willems)
XML-File" Version="1.0"/><globalsettings newtonframerate="300" gravity="9.800"
modelsolver="0" modelfriction="0" visualizejoints="False"
skyspheretexture="1.jpg"/><camerasettings mode="default" state="0" position="0.000
0.000 0.000" rotation="67.500 -37.500 0.000" zoom="-44.800"/><treecollision
filename="env_default.x" startmatrix="1.000 0.000 0.000 0.000 0.000 1.000 0.000
0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 1.00" massmatrix="0.000 0.000 0.000
0.000" color="0.000 0.000 0.000" lineardamp="0.000" angulardamp="0.000 0.000 0.000"
continuouscollision="False" caption="" springcount="0"
material="default"/><primitives count="4"><primitive0><box size="1.000 1.000 1.000"
freezed="False" startmatrix="1.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
0.000 1.000 0.000 0.000 2.000 0.000 1.00" massmatrix="0.000 0.000 0.000 0.000"
color="0.000 0.000 0.000" lineardamp="0.100" angulardamp="0.100 0.100 0.100"
continuouscollision="False" caption="" springcount="0"
material="default"/></primitive0><primitive1><box size="30.000 1.000 1.000"
freezed="False" startmatrix="1.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
0.000 1.000 0.000 0.000 1.000 0.000 1.00" massmatrix="200.000 33.333 15017.000
15017.000" color="0.239 0.929 0.067" lineardamp="0.100" angulardamp="0.100 0.100
0.100" continuouscollision="False" caption="mass=200" springcount="0"
material="default"/></primitive1><primitive2><box size="1.000 1.000 30.000"
freezed="False" startmatrix="1.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
0.000 1.000 0.000 0.000 1.000 20.000 1.00" massmatrix="2000.000 1.5017E005
1.5017E005 333.330" color="0.165 0.804 0.231" lineardamp="0.100" angulardamp="0.100
0.100 0.100" continuouscollision="False" caption="mass= 2000" springcount="0"
material="default"/></primitive2><primitive3><box size="1.000 1.000 1.000"
freezed="False" startmatrix="1.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
0.000 1.000 0.000 0.000 2.000 20.000 1.00" massmatrix="0.000 0.000 0.000 0.000"
color="0.635 0.412 0.435" lineardamp="0.100" angulardamp="0.100 0.100 0.100"
continuouscollision="False" caption="" springcount="0"
material="default"/></primitive3></primitives><ragdolls count="0"/><vehicles
count="0"/><buoyancyvolumes count="0"/><joints count="2"><joint0><hinge
pindir="0.000 1.000 0.000" damperenabled="False" k="128.000" d="4.000"
childbodytype="rigidbody" childbodyID="1" childbodysubID="0"
parentbodytype="rigidbody" parentbodyID="0" parentbodysubID="0" pivotpoint="0.000
2.000 0.000" collidable="False"><motor enabled="True" enablelimits="False"
acceleration="1.000" damping="0.250" minangle="-45.000"
maxangle="45.000"/></hinge></joint0><joint1><hinge pindir="0.000 1.000 0.000"
damperenabled="False" k="128.000" d="4.000" childbodytype="rigidbody"
childbodyID="3" childbodysubID="0" parentbodytype="rigidbody" parentbodyID="2"
parentbodysubID="0" pivotpoint="0.000 1.000 20.000" collidable="False"><motor
enabled="False" enablelimits="False" acceleration="1.000" damping="0.250"
minangle="-45.000" maxangle="45.000"/></hinge></joint1></joints><TMaterialManager
materialcount="1"><material0 name="default" settingssetcount="1" isspecial="False"
specialid="0" specialv1="0.000 0.000 0.000" specialv2="0.000 0.000 0.000"
specials1="0.000" specials2="0.000"><settingsset0 othermaterial="default"
collidable="1" staticfriction="1.000" kineticfriction="0.500" elasticity="0.400"
softness="0.050" continuouscollision="0"/></material0></TMaterialManager></root>
maybe you have a better idea of what does it means.