Validation Error only for data in UTF-8 in h:selectOneMeny

Question

There is a amazing bug in my jsf application. I create selectOneMenu component in the code

  private  Map<String,String> languages; //+getter
  private String language; //+getter/setter

  @PostConstruct
  public void init() {
    languages = new LinkedHashMap<String, String>();
    languages.put("Русский", "ru");
    languages.put("Казахский", "kz");
  }

and on the page

        <h:selectOneMenu id="language" value="#{bean.language}">
            <f:selectItems value="#{bean.languages}"/>
        </h:selectOneMenu>

and after submit everything is ok.But if I change itemValue from

 languages.put("Русский", "ru");

to

 languages.put("Русский", "рус.язык");

then after submit I got "Validation Error: Value is not valid". Why? I really don't understand.

I use jsf 2.1.7, application server - JBoss.