Fixes Mantis #3260. Thank you kindly, MCortez for a patch that:

llSetHoverHeight() should not clamp the x/y position of an object the way MoveTo does, 
and it should recalculate the absolute height to hover at as an object moves to reflect 
the current ground/water height under it.
Correctly implementing required adjusting the Physics interfaces and implementing at 
the physics plug-in level. The attached is a patch that correctly implements 
llSetHoverHeight() including updates to the ODE physics plug-in.

2 files changed, 12 insertions, 0 deletions

diff --git a/OpenSim/Region/Physics/POSPlugin/POSCharacter.cs b/OpenSim/Region/Physics/POSPlugin/POSCharacter.cs
index 4230a57..0320931 100644
--- a/OpenSim/Region/Physics/POSPlugin/POSCharacter.cs
+++ b/OpenSim/Region/Physics/POSPlugin/POSCharacter.cs
@@ -288,6 +288,12 @@ namespace OpenSim.Region.Physics.POSPlugin
             set { return; }
         }
 
+        public override float PIDHoverHeight { set { return; } }
+        public override bool PIDHoverActive { set { return; } }
+        public override PIDHoverType PIDHoverType { set { return; } }
+        public override float PIDHoverTau { set { return; } }
+
+
         public override void SubscribeEvents(int ms)
         {
         }
diff --git a/OpenSim/Region/Physics/POSPlugin/POSPrim.cs b/OpenSim/Region/Physics/POSPlugin/POSPrim.cs
index bf96c35..526a2c6 100644
--- a/OpenSim/Region/Physics/POSPlugin/POSPrim.cs
+++ b/OpenSim/Region/Physics/POSPlugin/POSPrim.cs
@@ -283,6 +283,12 @@ namespace OpenSim.Region.Physics.POSPlugin
             set { return; }
         }
 
+        public override float PIDHoverHeight { set { return; } }
+        public override bool PIDHoverActive { set { return; } }
+        public override PIDHoverType PIDHoverType { set { return; } }
+        public override float PIDHoverTau { set { return; } }
+
+
         public override void SubscribeEvents(int ms)
         {
         }