I am getting "value is not valid" when using <h:selectOneMenu + entity + <s:convertEntity.

My entity has hashCode and equals methods implemented:

<h:selectOneMenu id="muniUsuario" value="#{usuarioHome.instance.municipio}" required="true">
<s:selectItems value="#{listaMunicipios}" var="municipioSelecionado" label="#{municipioSelecionado.noMunicipio}" noSelectionLabel=""/>
<a:support eventsQueue="queueUsuario" event="onchange" bypassUpdates="false" ajaxSingle="true"/>                                                       <s:convertEntity />
</h:selectOneMenu>

Rendered page:
....
<option value="0">Vit&oacute;ria da Conquista</option>
....

WHY VALUE IS 0????

package br.com.infosolo.controle.util;

import static org.jboss.seam.ScopeType.APPLICATION;

import java.io.Serializable;
import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.Query;

import org.jboss.seam.annotations.In;
import org.jboss.seam.annotations.Logger;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.annotations.Transactional;
import org.jboss.seam.annotations.Unwrap;

import br.com.infosolo.snit.entidades.Municipio;

@Name("listaMunicipios")
@Scope(APPLICATION)
public class ListaMunicipios implements Serializable {
     @Logger
     private org.jboss.seam.log.Log log;     
     /**
      *
      */
     private static final long serialVersionUID = -3902172130442786620L;

     @In(value="entityManager")
     EntityManager em;
     
     List<Municipio> municipios;

     @Unwrap
     @Transactional
     public List<Municipio> getMunicipios(){
          if(municipios==null){
               Query query = em.createNamedQuery("municipio.retornarTodosMunicipios");
               municipios = query.getResultList();
               for(Municipio municipio : municipios){
                    log.info("Municipio carregado: {0} - {1}", municipio.getNuMunicipio(), municipio.getNoMunicipio());
               }
          }
          return municipios;
     }
}
----
I think maybe a problem? This works in seam 2.2.1.Final......