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diff --git a/src/DotNetOAuth/Messaging/StandardMessageExpirationBindingElement.cs b/src/DotNetOAuth/Messaging/StandardMessageExpirationBindingElement.cs
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+//-----------------------------------------------------------------------
+// <copyright file="StandardMessageExpirationBindingElement.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOAuth.Messaging {
+	using System;
+
+	/// <summary>
+	/// A message expiration enforcing binding element that supports messages
+	/// implementing the <see cref="IExpiringProtocolMessage"/> interface.
+	/// </summary>
+	internal class StandardMessageExpirationBindingElement : IChannelBindingElement {
+		/// <summary>
+		/// The default maximum message age to use if the default constructor is called.
+		/// </summary>
+		internal static readonly TimeSpan DefaultMaximumMessageAge = TimeSpan.FromMinutes(13);
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="StandardMessageExpirationBindingElement"/> class
+		/// with a default maximum message lifetime of 13 minutes.
+		/// </summary>
+		internal StandardMessageExpirationBindingElement()
+			: this(DefaultMaximumMessageAge) {
+		}
+
+		/// <summary>
+		/// Initializes a new instance of the <see cref="StandardMessageExpirationBindingElement"/> class.
+		/// </summary>
+		/// <param name="maximumAge">
+		/// <para>The maximum age a message implementing the 
+		/// <see cref="IExpiringProtocolMessage"/> interface can be before
+		/// being discarded as too old.</para>
+		/// <para>This time limit should take into account expected time skew for servers
+		/// across the Internet.  For example, if a server could conceivably have its
+		/// clock d = 5 minutes off UTC time, then any two servers could have
+		/// their clocks disagree by as much as 2*d = 10 minutes.
+		/// If a message should live for at least t = 3 minutes, 
+		/// this property should be set to (2*d + t) = 13 minutes.</para>
+		/// </param>
+		internal StandardMessageExpirationBindingElement(TimeSpan maximumAge) {
+			this.MaximumMessageAge = maximumAge;
+		}
+
+		#region IChannelBindingElement Properties
+
+		/// <summary>
+		/// Gets the protection offered by this binding element.
+		/// </summary>
+		/// <value><see cref="ChannelProtection.Expiration"/></value>
+		ChannelProtection IChannelBindingElement.Protection {
+			get { return ChannelProtection.Expiration; }
+		}
+
+		#endregion
+
+		/// <summary>
+		/// Gets the maximum age a message implementing the 
+		/// <see cref="IExpiringProtocolMessage"/> interface can be before
+		/// being discarded as too old.
+		/// </summary>
+		protected internal TimeSpan MaximumMessageAge {
+			get;
+			private set;
+		}
+
+		#region IChannelBindingElement Methods
+
+		/// <summary>
+		/// Sets the timestamp on an outgoing message.
+		/// </summary>
+		/// <param name="message">The outgoing message.</param>
+		void IChannelBindingElement.PrepareMessageForSending(IProtocolMessage message) {
+			IExpiringProtocolMessage expiringMessage = message as IExpiringProtocolMessage;
+			if (expiringMessage != null) {
+				expiringMessage.UtcCreationDate = DateTime.UtcNow;
+			}
+		}
+
+		/// <summary>
+		/// Reads the timestamp on a message and throws an exception if the message is too old.
+		/// </summary>
+		/// <param name="message">The incoming message.</param>
+		/// <exception cref="ExpiredMessageException">Thrown if the given message has already expired.</exception>
+		void IChannelBindingElement.PrepareMessageForReceiving(IProtocolMessage message) {
+			IExpiringProtocolMessage expiringMessage = message as IExpiringProtocolMessage;
+			if (expiringMessage != null) {
+				// Yes the UtcCreationDate is supposed to always be in UTC already,
+				// but just in case a given message failed to guarantee that, we do it here.
+				DateTime expirationDate = expiringMessage.UtcCreationDate.ToUniversalTime() + this.MaximumMessageAge;
+				if (expirationDate < DateTime.UtcNow) {
+					throw new ExpiredMessageException(expirationDate, expiringMessage);
+				}
+			}
+		}
+
+		#endregion
+	}
+}