BulletSim Physics Engine

[APPLICATION]: 
APPLICATION EXCEPTION DETECTED: System.UnhandledExceptionEventArgs

Exception: System.DllNotFoundException: lib32/libBulletSim.so
  at (wrapper managed-to-native) OpenSim.Region.Physics.BulletSPlugin.BulletSimAPI:SetDebugLogCallback (OpenSim.Region.Physics.BulletSPlugin.BulletSimAPI/DebugLogCallback)
  at OpenSim.Region.Physics.BulletSPlugin.BSScene.Initialise (IMesher meshmerizer, IConfigSource config) [0x00000] in <filename unknown>:0 
  at OpenSim.Region.Physics.Manager.PhysicsPluginManager.GetPhysicsScene (System.String physEngineName, System.String meshEngineName, IConfigSource config, System.String regionName) [0x00000] in <filename unknown>:0 
  at OpenSim.Region.ClientStack.RegionApplicationBase.GetPhysicsScene (System.String engine, System.String meshEngine, IConfigSource config, System.String osSceneIdentifier) [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSimBase.GetPhysicsScene (System.String osSceneIdentifier) [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSimBase.SetupScene (OpenSim.Framework.RegionInfo regionInfo, Int32 proxyOffset, IConfigSource configSource, IClientNetworkServer& clientServer) [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSimBase.CreateRegion (OpenSim.Framework.RegionInfo regionInfo, Boolean portadd_flag, Boolean do_post_init, IScene& mscene) [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSimBase.CreateRegion (OpenSim.Framework.RegionInfo regionInfo, Boolean portadd_flag, IScene& scene) [0x00000] in <filename unknown>:0 
  at OpenSim.ApplicationPlugins.LoadRegions.LoadRegionsPlugin.PostInitialise () [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSimBase.StartupSpecific () [0x00000] in <filename unknown>:0 
  at OpenSim.OpenSim.StartupSpecific () [0x00000] in <filename unknown>:0 
  at OpenSim.Framework.Servers.BaseOpenSimServer.Startup () [0x00000] in <filename unknown>:0 
  at OpenSim.Application.Main (System.String[] args) [0x00000] in <filename unknown>:0