Input keyboard localization

Hello, I try to use RadNumericBox with different culture settings. For example, I use "ru-RU" culture (Number separator is ","):

var culture = new CultureInfo("ru-RU");
Windows.Globalization.ApplicationLanguages.PrimaryLanguageOverride = culture.Name;
CultureInfo.DefaultThreadCurrentCulture = culture;
CultureInfo.DefaultThreadCurrentUICulture = culture;

 I set primitives:CultureService.CultureName="ru-RU" at the control, but I still see "." separator on the keyboard and I can't input this separator. Could you explain me where I made a mistake?

Thanks.