What changed with Dispose in 2005 RC?

We have a suite of programs currently with Visual Studio 2005 Beta 2, Today I uninstalled Beta 2 and upgraded to the Release Canidate:

Using this example code:

public ref class PlaybackCtrl : public System::Windows::Forms::UserControl
{
 protected:
  virtual void Dispose(Boolean disposing) override
  {
   if (disposing && components)
   {
    components->Dispose();
   }
   __super::Dispose(disposing);
  }
}

I end up with errors like: error C2605: 'Dispose' : this method is reserved within a managed class

Not quite sure I understand cause it is a managed class....

Also trying to call Dispose on Managed DX objects gives me a similar error:

error C2039: 'Dispose' : is not a member of 'Microsoft::DirectX::Direct3D::VertexBuffer'

But I see dispose in Intellisense, so not sure what the deal is...

Thanks for any info!