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diff --git a/src/DotNetOpenAuth.Core/Messaging/EmptyList.cs b/src/DotNetOpenAuth.Core/Messaging/EmptyList.cs
new file mode 100644
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+++ b/src/DotNetOpenAuth.Core/Messaging/EmptyList.cs
@@ -0,0 +1,211 @@
+//-----------------------------------------------------------------------
+// <copyright file="EmptyList.cs" company="Andrew Arnott">
+//     Copyright (c) Andrew Arnott. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.Messaging {
+	using System;
+	using System.Collections.Generic;
+	using System.Diagnostics.CodeAnalysis;
+
+	/// <summary>
+	/// An empty, read-only list.
+	/// </summary>
+	/// <typeparam name="T">The type the list claims to include.</typeparam>
+	[Serializable]
+	internal class EmptyList<T> : IList<T> {
+		/// <summary>
+		/// The singleton instance of the empty list.
+		/// </summary>
+		internal static readonly EmptyList<T> Instance = new EmptyList<T>();
+
+		/// <summary>
+		/// Prevents a default instance of the EmptyList class from being created.
+		/// </summary>
+		private EmptyList() {
+		}
+
+		/// <summary>
+		/// Gets the number of elements contained in the <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </summary>
+		/// <value></value>
+		/// <returns>
+		/// The number of elements contained in the <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </returns>
+		public int Count {
+			get { return 0; }
+		}
+
+		/// <summary>
+		/// Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only.
+		/// </summary>
+		/// <value></value>
+		/// <returns>true if the <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only; otherwise, false.
+		/// </returns>
+		public bool IsReadOnly {
+			get { return true; }
+		}
+
+		#region IList<T> Members
+
+		/// <summary>
+		/// Gets or sets the <typeparamref name="T"/> at the specified index.
+		/// </summary>
+		/// <param name="index">The index of the element in the list to change.</param>
+		public T this[int index] {
+			get {
+				throw new ArgumentOutOfRangeException("index");
+			}
+
+			set {
+				throw new ArgumentOutOfRangeException("index");
+			}
+		}
+
+		/// <summary>
+		/// Determines the index of a specific item in the <see cref="T:System.Collections.Generic.IList`1"/>.
+		/// </summary>
+		/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.IList`1"/>.</param>
+		/// <returns>
+		/// The index of <paramref name="item"/> if found in the list; otherwise, -1.
+		/// </returns>
+		public int IndexOf(T item) {
+			return -1;
+		}
+
+		/// <summary>
+		/// Inserts an item to the <see cref="T:System.Collections.Generic.IList`1"/> at the specified index.
+		/// </summary>
+		/// <param name="index">The zero-based index at which <paramref name="item"/> should be inserted.</param>
+		/// <param name="item">The object to insert into the <see cref="T:System.Collections.Generic.IList`1"/>.</param>
+		/// <exception cref="T:System.ArgumentOutOfRangeException">
+		/// 	<paramref name="index"/> is not a valid index in the <see cref="T:System.Collections.Generic.IList`1"/>.
+		/// </exception>
+		/// <exception cref="T:System.NotSupportedException">
+		/// The <see cref="T:System.Collections.Generic.IList`1"/> is read-only.
+		/// </exception>
+		public void Insert(int index, T item) {
+			throw new NotSupportedException();
+		}
+
+		/// <summary>
+		/// Removes the <see cref="T:System.Collections.Generic.IList`1"/> item at the specified index.
+		/// </summary>
+		/// <param name="index">The zero-based index of the item to remove.</param>
+		/// <exception cref="T:System.ArgumentOutOfRangeException">
+		/// 	<paramref name="index"/> is not a valid index in the <see cref="T:System.Collections.Generic.IList`1"/>.
+		/// </exception>
+		/// <exception cref="T:System.NotSupportedException">
+		/// The <see cref="T:System.Collections.Generic.IList`1"/> is read-only.
+		/// </exception>
+		[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Justification = "Code Contracts ccrewrite does this.")]
+		public void RemoveAt(int index) {
+			throw new ArgumentOutOfRangeException("index");
+		}
+
+		#endregion
+
+		#region ICollection<T> Members
+
+		/// <summary>
+		/// Adds an item to the <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </summary>
+		/// <param name="item">The object to add to the <see cref="T:System.Collections.Generic.ICollection`1"/>.</param>
+		/// <exception cref="T:System.NotSupportedException">
+		/// The <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only.
+		/// </exception>
+		[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Justification = "Code Contracts ccrewrite does this.")]
+		public void Add(T item) {
+			throw new NotSupportedException();
+		}
+
+		/// <summary>
+		/// Removes all items from the <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </summary>
+		/// <exception cref="T:System.NotSupportedException">
+		/// The <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only.
+		/// </exception>
+		public void Clear() {
+			throw new NotSupportedException();
+		}
+
+		/// <summary>
+		/// Determines whether the <see cref="T:System.Collections.Generic.ICollection`1"/> contains a specific value.
+		/// </summary>
+		/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.ICollection`1"/>.</param>
+		/// <returns>
+		/// true if <paramref name="item"/> is found in the <see cref="T:System.Collections.Generic.ICollection`1"/>; otherwise, false.
+		/// </returns>
+		public bool Contains(T item) {
+			return false;
+		}
+
+		/// <summary>
+		/// Copies the elements of the <see cref="T:System.Collections.Generic.ICollection`1"/> to an <see cref="T:System.Array"/>, starting at a particular <see cref="T:System.Array"/> index.
+		/// </summary>
+		/// <param name="array">The one-dimensional <see cref="T:System.Array"/> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.ICollection`1"/>. The <see cref="T:System.Array"/> must have zero-based indexing.</param>
+		/// <param name="arrayIndex">The zero-based index in <paramref name="array"/> at which copying begins.</param>
+		/// <exception cref="T:System.ArgumentNullException">
+		/// 	<paramref name="array"/> is null.
+		/// </exception>
+		/// <exception cref="T:System.ArgumentOutOfRangeException">
+		/// 	<paramref name="arrayIndex"/> is less than 0.
+		/// </exception>
+		/// <exception cref="T:System.ArgumentException">
+		/// 	<paramref name="array"/> is multidimensional.
+		/// -or-
+		/// <paramref name="arrayIndex"/> is equal to or greater than the length of <paramref name="array"/>.
+		/// -or-
+		/// The number of elements in the source <see cref="T:System.Collections.Generic.ICollection`1"/> is greater than the available space from <paramref name="arrayIndex"/> to the end of the destination <paramref name="array"/>.
+		/// -or-
+		/// Type <typeparamref name="T"/> cannot be cast automatically to the type of the destination <paramref name="array"/>.
+		/// </exception>
+		public void CopyTo(T[] array, int arrayIndex) {
+		}
+
+		/// <summary>
+		/// Removes the first occurrence of a specific object from the <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </summary>
+		/// <param name="item">The object to remove from the <see cref="T:System.Collections.Generic.ICollection`1"/>.</param>
+		/// <returns>
+		/// true if <paramref name="item"/> was successfully removed from the <see cref="T:System.Collections.Generic.ICollection`1"/>; otherwise, false. This method also returns false if <paramref name="item"/> is not found in the original <see cref="T:System.Collections.Generic.ICollection`1"/>.
+		/// </returns>
+		/// <exception cref="T:System.NotSupportedException">
+		/// The <see cref="T:System.Collections.Generic.ICollection`1"/> is read-only.
+		/// </exception>
+		public bool Remove(T item) {
+			return false;
+		}
+
+		#endregion
+
+		#region IEnumerable<T> Members
+
+		/// <summary>
+		/// Returns an enumerator that iterates through the collection.
+		/// </summary>
+		/// <returns>
+		/// A <see cref="T:System.Collections.Generic.IEnumerator`1"/> that can be used to iterate through the collection.
+		/// </returns>
+		public IEnumerator<T> GetEnumerator() {
+			return System.Linq.Enumerable.Empty<T>().GetEnumerator();
+		}
+
+		#endregion
+
+		#region IEnumerable Members
+
+		/// <summary>
+		/// Returns an enumerator that iterates through a collection.
+		/// </summary>
+		/// <returns>
+		/// An <see cref="T:System.Collections.IEnumerator"/> object that can be used to iterate through the collection.
+		/// </returns>
+		System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() {
+			return EmptyEnumerator.Instance;
+		}
+
+		#endregion
+	}
+}