HttpRequest login method and Push

Hi all!

Latest Vaadin framework. I have application which use HttpRequest login metod.

@Theme("mytheme")
@Widgetset("org.mycompany.logintest.MyAppWidgetset")
@CDIUI("")
@PreserveOnRefresh
public class MyUI extends UI {

    @Override
    protected void init(VaadinRequest vaadinRequest) {
        try {
            VaadinServletService.getCurrentServletRequest().login("user", "password");
            }  catch (ServletException ex) {
                logger.info(MessageFormat.format("Login failed for user {0}", "user"));
        }
    }
}

All work fine. But if i add @Push annotation to my main class login method stop work. Just nothing happens!
Bug or feature?

Thanks.