diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index a3039721d2..4c54f9ff27 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -174,15 +174,19 @@ public sealed class BSCharacter : BSPhysObject
         PhysScene.PE.UpdateSingleAabb(PhysScene.World, PhysBody);
 
         // Do this after the object has been added to the world
-        PhysBody.collisionType = CollisionType.Avatar;
+        if (BSParam.AvatarToAvatarCollisionsByDefault)
+            PhysBody.collisionType = CollisionType.Avatar;
+        else
+            PhysBody.collisionType = CollisionType.PhantomToOthersAvatar;
+
         PhysBody.ApplyCollisionMask(PhysScene);
     }
 
-
     public override void RequestPhysicsterseUpdate()
     {
         base.RequestPhysicsterseUpdate();
     }
+
     // No one calls this method so I don't know what it could possibly mean
     public override bool Stopped { get { return false; } }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
index 867d6ff903..e7f4deffe0 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
@@ -132,6 +132,7 @@ public static class BSParam
     public static float PhysicsUnmanLoggingFrames { get; private set; }
 
     // Avatar parameters
+    public static bool AvatarToAvatarCollisionsByDefault { get; private set; }
     public static float AvatarFriction { get; private set; }
     public static float AvatarStandingFriction { get; private set; }
     public static float AvatarAlwaysRunFactor { get; private set; }
@@ -571,6 +572,8 @@ public static class BSParam
         new ParameterDefn<float>("TerrainCollisionMargin", "Margin where collision checking starts" ,
             0.04f ),
 
+        new ParameterDefn<bool>("AvatarToAvatarCollisionsByDefault", "Should avatars collide with other avatars by default?",
+            true),
         new ParameterDefn<float>("AvatarFriction", "Factor to reduce movement against an avatar. Changed on avatar recreation.",
             0.2f ),
         new ParameterDefn<float>("AvatarStandingFriction", "Avatar friction when standing. Changed on avatar recreation.",
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BulletSimData.cs b/OpenSim/Region/Physics/BulletSPlugin/BulletSimData.cs
index 85ef64b104..59324611d6 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BulletSimData.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BulletSimData.cs
@@ -190,6 +190,7 @@ public class BulletHMapInfo
 public enum CollisionType
 {
     Avatar,
+    PhantomToOthersAvatar, // An avatar that it phantom to other avatars but not to anything else
     Groundplane,
     Terrain,
     Static,
@@ -231,7 +232,12 @@ public static Dictionary<CollisionType, CollisionTypeFilterGroup> CollisionTypeM
     { CollisionType.Avatar,
                 new CollisionTypeFilterGroup(CollisionType.Avatar,
                                 (uint)CollisionFilterGroups.BCharacterGroup,
-                                (uint)(CollisionFilterGroups.BAllGroup & ~CollisionFilterGroups.BCharacterGroup))
+                                (uint)(CollisionFilterGroups.BAllGroup))
+    },
+    { CollisionType.PhantomToOthersAvatar,
+        new CollisionTypeFilterGroup(CollisionType.PhantomToOthersAvatar,
+                                     (uint)CollisionFilterGroups.BCharacterGroup,
+                                     (uint)(CollisionFilterGroups.BAllGroup & ~CollisionFilterGroups.BCharacterGroup))
     },
     { CollisionType.Groundplane,
                 new CollisionTypeFilterGroup(CollisionType.Groundplane,
diff --git a/bin/OpenSim.ini.example b/bin/OpenSim.ini.example
index 573180abec..037487779b 100644
--- a/bin/OpenSim.ini.example
+++ b/bin/OpenSim.ini.example
@@ -619,6 +619,11 @@
     ; ForwardOfflineGroupMessages = true
 
 
+[BulletSim]
+    ;# {AvatarToAvatarCollisionsByDefault} {[Startup]physics:BulletSim} {Should avatars collide with each other?} {true false} true
+    AvatarToAvatarCollisionsByDefault = true
+
+
 [ODEPhysicsSettings]
     ;# {mesh_sculpted_prim} {[Startup]physics:OpenDynamicsEngine} {Mesh sculpties so they collide as they look?} {true false} true
     ;; Do we want to mesh sculpted prim to collide like they look?
diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index 0be4af53d1..e89fa0aed5 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -1045,6 +1045,9 @@
     ;   magnifications use lots of memory.
     TerrainMeshMagnification = 2
 
+    ; Should avatars collide with each other?
+    AvatarToAvatarCollisionsByDefault = true
+
     ; Avatar physics height adjustments.
     ;   http://opensimulator.org/wiki/BulletSim#Adjusting_Avatar_Height
     AvatarHeightLowFudge = 0      ; Adjustment at low end of height range