java中request.setAttribute()怪异问题

public class JstlCoreAction extends Action { public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
request.setAttribute("v1", 1);
request.setAttribute("v2", 2);

return mapping.findForward("success");
}
}红色的地方是MyEclipse指出的错误，可是在其他的project中却没问题，甚为不解？（上面相关的包没列出来）
求大侠帮帮忙看看，
谢谢了！