2 files changed, 24 insertions, 6 deletions
diff --git a/src/DotNetOAuth.Test/Messaging/Reflection/MessageDictionaryTest.cs b/src/DotNetOAuth.Test/Messaging/Reflection/MessageDictionaryTest.cs
index f798bde..f6b1f38 100644
--- a/src/DotNetOAuth.Test/Messaging/Reflection/MessageDictionaryTest.cs
+++ b/src/DotNetOAuth.Test/Messaging/Reflection/MessageDictionaryTest.cs
@@ -12,6 +12,7 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 	using DotNetOAuth.Messaging;
 	using DotNetOAuth.Messaging.Reflection;
 	using Microsoft.VisualStudio.TestTools.UnitTesting;
+	using System.Xml;
 
 	[TestClass]
 	public class MessageDictionaryTest : MessagingTestBase {
@@ -37,7 +38,7 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 			IDictionary<string, string> target = new MessageDictionary(this.message);
 			Collection<string> expected = new Collection<string> {
 				this.message.Age.ToString(),
-				this.message.Timestamp.ToString(),
+				XmlConvert.ToString(DateTime.SpecifyKind(this.message.Timestamp, DateTimeKind.Utc), XmlDateTimeSerializationMode.Utc),
 			};
 			CollectionAssert<string>.AreEquivalent(expected, target.Values);
 
@@ -49,7 +50,7 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 				this.message.Age.ToString(),
 				this.message.Location.AbsoluteUri,
 				this.message.Name,
-				this.message.Timestamp.ToString(),
+				XmlConvert.ToString(DateTime.SpecifyKind(this.message.Timestamp, DateTimeKind.Utc), XmlDateTimeSerializationMode.Utc),
 				"a",
 			};
 			CollectionAssert<string>.AreEquivalent(expected, target.Values);
@@ -80,7 +81,7 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 		[TestMethod]
 		public void ItemTest() {
 			IDictionary<string, string> target = new MessageDictionary(this.message);
-			
+
 			// Test setting of declared message properties.
 			this.message.Age = 15;
 			Assert.AreEqual("15", target["age"]);
@@ -194,7 +195,7 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 			Assert.IsTrue(target.Remove("Name"));
 			Assert.IsNull(this.message.Name);
 			Assert.IsFalse(target.Remove("Name"));
-			
+
 			Assert.IsFalse(target.Remove("extra"));
 			target["extra"] = "value";
 			Assert.IsTrue(target.Remove("extra"));
diff --git a/src/DotNetOAuth.Test/Messaging/Reflection/MessagePartTests.cs b/src/DotNetOAuth.Test/Messaging/Reflection/MessagePartTests.cs
index 646599c..1d7e1b8 100644
--- a/src/DotNetOAuth.Test/Messaging/Reflection/MessagePartTests.cs
+++ b/src/DotNetOAuth.Test/Messaging/Reflection/MessagePartTests.cs
@@ -16,12 +16,29 @@ namespace DotNetOAuth.Test.Messaging.Reflection {
 			[MessagePart(IsRequired = false)]
 			internal int optionalInt;
 		}
+		class MessageWithNullableOptionalStruct {
+			/// <summary>
+			/// Optional structs like int must be nullable for Optional to make sense.
+			/// </summary>
+			[MessagePart(IsRequired = false)]
+			internal int? optionalInt;
+		}
+		
 
 		[TestMethod, ExpectedException(typeof(ArgumentException))]
 		public void OptionalNonNullableStruct() {
-			FieldInfo field = typeof(MessageWithNonNullableOptionalStruct).GetField("optionalInt", BindingFlags.NonPublic | BindingFlags.Instance);
+			ParameterizedMessageTypeTest(typeof(MessageWithNonNullableOptionalStruct));
+		}
+
+		[TestMethod]
+		public void OptionalNullableStruct() {
+			ParameterizedMessageTypeTest(typeof(MessageWithNullableOptionalStruct));
+		}
+
+		private void ParameterizedMessageTypeTest(Type messageType) {
+			FieldInfo field = messageType.GetField("optionalInt", BindingFlags.NonPublic | BindingFlags.Instance);
 			MessagePartAttribute attribute = field.GetCustomAttributes(typeof(MessagePartAttribute), true).OfType<MessagePartAttribute>().Single();
-			new MessagePart(field, attribute); // should recognize invalid optional non-nullable struct
+			new MessagePart(field, attribute);
 		}
 	}
 }