I was using System.Web.Mvc 184.108.40.206 in my project (I installed manually the package with "Install-Package Microsoft.AspNet.Mvc -Version 5.2.3"). Well, I gone to update all packages:
VS Community 2013: Tools -> NuGet Package Manager -> Manage NuGet Packages for Solution... -> Updates -> nuget.org -> Update All
I have installed System.Web.Mvc v4 now. What happened?