diff --git a/UnitTestDll/test_enum.cs b/UnitTestDll/test_enum.cs
index f5a58a2..7fe60dc 100644
--- a/UnitTestDll/test_enum.cs
+++ b/UnitTestDll/test_enum.cs
@@ -4,6 +4,7 @@
 using System.Text;
 using UnitTest;
 using System.Reflection;
+using System.IO;
 
 namespace UnitTestDll
 {
@@ -110,6 +111,13 @@ static void UnitTest_19()
             object obj = 1;
             Test(obj);
         }
+        
+        static void UnitTest_20()
+        {
+            uint ui = 1;
+			MemoryStream str = new MemoryStream ();
+			str.Write (new byte[]{0}, 0, (int)ui);
+        }
     }