How to troubleshoot .net3.5 WinForm localization

If I use .net 4 or 4.5 it works well, but when I use .net3.5 it's not work

Step to reproduce this problem:

• create simply winform project Form1.Text = Form1
• set in Form1.Localizable = true
• change Form1.Language = English
• change Form1.Text = EnglishFromText
• change Form1.Language = Russian
• change Form1.Text = RussianFromText ...
• for every from language was generated resource file Form1.en.resx, Form1.ru.resx, ...

• next i modify Form1 constructor to next:

  Thread.CurrentThread.CurrentUICulture=newSystem.Globalization.CultureInfo("en");InitializeComponent();

• or next:

  Thread.CurrentThread.CurrentUICulture=newSystem.Globalization.CultureInfo("ru");InitializeComponent();

• when I set Target Framework as .NET Framework 4 in Visual Studio Project Properties after run app in Form title is "EnglishFromText" (or "RussianFromText")

• but when I set Target Framework as .NET Framework 3.5 after run app in Form title is "Form1"

• I don't know why but when use .NET Framework 3.5, files Form1.en.resx, Form1.ru.resx ignored and used values from Form1.resx