diff --git a/Nuclex.Support (net-4.0).csproj b/Nuclex.Support (net-4.0).csproj
index 292ab3f..b365295 100644
--- a/Nuclex.Support (net-4.0).csproj	
+++ b/Nuclex.Support (net-4.0).csproj	
@@ -388,9 +388,7 @@
       <Link>Foundation.snk</Link>
     </None>
   </ItemGroup>
-  <ItemGroup>
-    <Folder Include="Source\Cloning\" />
-  </ItemGroup>
+  <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
diff --git a/Source/Collections/Deque.cs b/Source/Collections/Deque.cs
index 513631c..6731447 100644
--- a/Source/Collections/Deque.cs
+++ b/Source/Collections/Deque.cs
@@ -35,7 +35,7 @@ namespace Nuclex.Support.Collections {
   ///   <para>
   ///     Therefore, it's not only good at coping with lists that are modified at their
   ///     beginning, but also at handling huge data sets since enlarging the deque doesn't
-  ///     require items to be copied around and still can be accessed by index.
+  ///     require items to be copied around and it still can be accessed by index.
   ///   </para>
   /// </remarks>
   public partial class Deque<ItemType> : IList<ItemType>, IList {
diff --git a/Source/Collections/MultiDictionary.Test.cs b/Source/Collections/MultiDictionary.Test.cs
index 776b34a..9fce363 100644
--- a/Source/Collections/MultiDictionary.Test.cs
+++ b/Source/Collections/MultiDictionary.Test.cs
@@ -18,11 +18,11 @@ License along with this library
 */
 #endregion
 
+#if UNITTEST
+
 using System;
 using System.Collections.Generic;
 
-#if UNITTEST
-
 using NUnit.Framework;
 using NMock;
 
diff --git a/Source/Collections/MultiDictionary.cs b/Source/Collections/MultiDictionary.cs
index 11a5455..f72320c 100644
--- a/Source/Collections/MultiDictionary.cs
+++ b/Source/Collections/MultiDictionary.cs
@@ -327,6 +327,10 @@ namespace Nuclex.Support.Collections {
     public ICollection<TValue> this[TKey key] {
       get { return this.typedDictionary[key]; }
       set {
+        if(value == null) {
+          this.typedDictionary.Remove(key);
+        }
+
         ICollection<TValue> currentValues;
         if(this.typedDictionary.TryGetValue(key, out currentValues)) {
           currentValues.Clear();
diff --git a/Source/Collections/WeakCollection.cs b/Source/Collections/WeakCollection.cs
index 0f6fa78..2716278 100644
--- a/Source/Collections/WeakCollection.cs
+++ b/Source/Collections/WeakCollection.cs
@@ -119,7 +119,7 @@ namespace Nuclex.Support.Collections {
     ///   Comparer used to identify and compare items to each other
     /// </param>
     public WeakCollection(
-        IList<WeakReference<ItemType>> items, IEqualityComparer<ItemType> comparer
+      IList<WeakReference<ItemType>> items, IEqualityComparer<ItemType> comparer
     ) {
       this.items = items;
       this.comparer = comparer;