diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
index a70914015f..c1411310b3 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
@@ -53,6 +53,7 @@ using System.Drawing;
 using System.Globalization;
 using System.Reflection;
 using System.Runtime.Remoting.Lifetime;
+using System.Security.Cryptography;
 using System.Text;
 using System.Text.RegularExpressions;
 using System.Threading;