It is really weird... I tested that on clean machine and everything worked well.
I can only guess that you have another add-in or package that executed the following line of code:
Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US")
And then, all assemblies in Visual Studio run their code in another locale.
Try to turn off another add-ins and try again.
Thank you,
Misha Zhutov
http://submain.com - .NET Developer Tools | Microsoft VB MVP