opensim/bin/OpenSim.Region.Physics.BulletSPlugin.dll.config

<configuration>
  <dllmap os="windows" cpu="x86" dll="BulletSim" target="BulletSim" />
  <dllmap os="windows" cpu="x86-64,ia64" dll="BulletSim" target="BulletSim-x86_64" />
  <dllmap os="!windows,osx" cpu="x86" dll="BulletSim" target="libBulletSim" />
  <dllmap os="!windows,osx" cpu="x86-64,ia64" dll="BulletSim" target="libBulletSim-x86_64" />
</configuration>