diff --git a/OpenSim/Region/ScriptEngine/Common/LSL_Types.cs b/OpenSim/Region/ScriptEngine/Common/LSL_Types.cs
index 21acac2f6d..4fff717e31 100644
--- a/OpenSim/Region/ScriptEngine/Common/LSL_Types.cs
+++ b/OpenSim/Region/ScriptEngine/Common/LSL_Types.cs
@@ -126,6 +126,11 @@ namespace OpenSim.Region.ScriptEngine.Common
                 return (x == vector.x && x == vector.x && z == vector.z);
             }
 
+            public static Vector3 operator -(Vector3 vector)
+            {
+                return new Vector3(-vector.x, -vector.y, -vector.z);
+            }
+
             #endregion
 
             #region Vector & Vector Math
diff --git a/OpenSim/Tests/OpenSim/Region/ScriptEngine/Common/LSL_TypesTestVector3.cs b/OpenSim/Tests/OpenSim/Region/ScriptEngine/Common/LSL_TypesTestVector3.cs
index cadee9348d..0a41f92c2e 100644
--- a/OpenSim/Tests/OpenSim/Region/ScriptEngine/Common/LSL_TypesTestVector3.cs
+++ b/OpenSim/Tests/OpenSim/Region/ScriptEngine/Common/LSL_TypesTestVector3.cs
@@ -29,6 +29,7 @@ using System.Collections.Generic;
 using NUnit.Framework;
 using OpenSim.Tests.Common;
 using OpenSim.Region.ScriptEngine.Common;
+using vector = OpenSim.Region.ScriptEngine.Common.LSL_Types.Vector3;
 
 namespace OpenSim.Region.ScriptEngine.Common.Tests
 {
@@ -39,7 +40,6 @@ namespace OpenSim.Region.ScriptEngine.Common.Tests
         /// Tests for Vector3
         /// </summary>
         [Test]
-
         public void TestDotProduct()
         {
             // The numbers we test for.
@@ -54,9 +54,16 @@ namespace OpenSim.Region.ScriptEngine.Common.Tests
             foreach (KeyValuePair<string, double> ex in expectsSet)
             {
                 parts = ex.Key.Split(delim, System.StringSplitOptions.None);
-                result = new LSL_Types.Vector3(parts[0]) * new LSL_Types.Vector3(parts[1]);
+                result = new vector(parts[0]) * new vector(parts[1]);
                 Assert.AreEqual(ex.Value, result);
             }
         }
+
+        [Test]
+        public void TestUnaryMinusOperator()
+        {
+            Assert.AreEqual(new vector(-1, -1, -1), - (new vector(1, 1, 1)));
+            Assert.AreEqual(new vector(0, 0, 0), - (new vector(0, 0, 0)));
+        }
     }
 }