diff --git a/snippets/VS2010/Nemerle.Compiler.Utils/Nemerle.Completion2/Engine/Engine-main.n b/snippets/VS2010/Nemerle.Compiler.Utils/Nemerle.Completion2/Engine/Engine-main.n
index c82b255d78..7971837602 100644
--- a/snippets/VS2010/Nemerle.Compiler.Utils/Nemerle.Completion2/Engine/Engine-main.n
+++ b/snippets/VS2010/Nemerle.Compiler.Utils/Nemerle.Completion2/Engine/Engine-main.n
@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.IO;
 using System.Diagnostics;
 using System.Linq;
@@ -52,7 +52,7 @@ namespace Nemerle.Completion2
 
     public Close() : void
     {
-      AsyncWorker.AddWork(AsyncRequest(AsyncRequestType.CloseProject, this, null, _ => ()));
+      AsyncWorker.AddWork(AsyncRequest(AsyncRequestType.CloseProject, this, null, _ => CleanUpTypes()));
     }
 
     // HACK: see usings
diff --git a/snippets/VS2010/Nemerle.VisualStudio/LanguageService/NemerleSource.cs b/snippets/VS2010/Nemerle.VisualStudio/LanguageService/NemerleSource.cs
index ee38a6502d..dd0b1733af 100644
--- a/snippets/VS2010/Nemerle.VisualStudio/LanguageService/NemerleSource.cs
+++ b/snippets/VS2010/Nemerle.VisualStudio/LanguageService/NemerleSource.cs
@@ -596,10 +596,6 @@ public override ParseRequest BeginParse(int line, int idx, TokenInfo info, Parse
 
     public override void Dispose()
     {
-      SmartIndent = null;
-      MethodData = null;
-      _tipAsyncRequest = null;
-
       if (ProjectInfo != null)
       {
         ProjectInfo.RemoveEditableSource(this);
@@ -617,6 +613,22 @@ public override void Dispose()
         ProjectInfo = null;
       }
 
+      SmartIndent = null;
+      MethodData = null;
+      _tipAsyncRequest = null;
+      CompileUnit = null;
+      Declarations = null;
+      Service = null;
+
+      if (_relocationRequestsQueue != null)
+        _relocationRequestsQueue.Clear();
+
+      if (TypeLocations != null)
+        TypeLocations.Clear();
+
+      if (MethodsTypeLocations != null)
+        MethodsTypeLocations.Clear();
+
       base.Dispose();
     }
 
diff --git a/snippets/VS2010/Nemerle.VisualStudio/Project/NemerleProjectNode.cs b/snippets/VS2010/Nemerle.VisualStudio/Project/NemerleProjectNode.cs
index 0ec718ad02..611dfbddc8 100644
--- a/snippets/VS2010/Nemerle.VisualStudio/Project/NemerleProjectNode.cs
+++ b/snippets/VS2010/Nemerle.VisualStudio/Project/NemerleProjectNode.cs
@@ -757,7 +757,11 @@ protected override void Dispose(bool disposing)
 		{
 			if (!_suppressDispose)
 			{
-				ProjectInfo.Close();
+				if (_projectInfo != null)
+				{
+					_projectInfo.Close();
+					_projectInfo = null;
+				}
 				base.Dispose(disposing);
 			}
 		}