diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Runtime/LSL_Constants.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Runtime/LSL_Constants.cs
index db3df46375..7d80dcbf27 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Runtime/LSL_Constants.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Runtime/LSL_Constants.cs
@@ -412,6 +412,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.ScriptBase
         public const int PRIM_SLICE = 35;
         public const int PRIM_SPECULAR = 36;
         public const int PRIM_NORMAL = 37;
+        public const int PRIM_ALPHA_MODE = 38;
         public const int PRIM_TEXGEN_DEFAULT = 0;
         public const int PRIM_TEXGEN_PLANAR = 1;