diff --git a/PorygonSharp/UserData/UserDataHandler.cs b/PorygonSharp/UserData/UserDataHandler.cs
index 7a17121..7ca5f9d 100644
--- a/PorygonSharp/UserData/UserDataHandler.cs
+++ b/PorygonSharp/UserData/UserDataHandler.cs
@@ -30,8 +30,8 @@ namespace PorygonSharp.UserData
                 });
                 var setter = new SetterDelegate((ptr, val) =>
                 {
-                    var evalValue = new EvalValue(val).GetObjectValue();
-                    var obj   = GCHandle.FromIntPtr(ptr).Target;
+                    var obj = GCHandle.FromIntPtr(ptr).Target;
+                    var evalValue = Convert.ChangeType(new EvalValue(val).GetObjectValue(), field.FieldType);
                     field.SetValue(obj, evalValue);
                 });
                 var scriptType = ScriptType.ScriptType.GetScriptType(field.FieldType);
diff --git a/PorygonSharpTests/UnitTest1.cs b/PorygonSharpTests/UnitTest1.cs
index 7a8f20e..deba67a 100644
--- a/PorygonSharpTests/UnitTest1.cs
+++ b/PorygonSharpTests/UnitTest1.cs
@@ -138,12 +138,35 @@ end
             }
         }
 
+        [Test]
+        public void Test10()
+        {
+            UserDataHandler.RegisterType("testObject", typeof(UserDataTestObject));
+            using (var script = Script.CreateScript(@"
+function test(testObject v)
+    v['Foo'] = 20000
+end
+"))
+            {
+                var diags = script.Diagnostics.GetDiagnostics();
+                foreach (var diag in diags)
+                {
+                    throw new Exception(diag.GetCode().ToString());
+                }
+
+                script.Evaluate();
+
+                var parameter = new UserDataTestObject();
+                script.CallFunction("test", parameter);
+                Assert.AreEqual(20000, parameter.Foo);
+            }
+        }
+
         [Test]
         public void TestHash()
         {
             var hash = HashedString.ScriptHash("Foo");
             Assert.AreEqual(193501609, hash);
         }
-
     }
 }
\ No newline at end of file