combobox RichFaces problem

[machinemuse]

need to load a combobox RichFaces with the result of another combobox, but the event does not work to charge the other with the result of the first combo.

<rich:comboBox id="origen" value="${combo.idOrigen}" directInputSuggestions="true" defaultLabel="Seleccione origen" width="219">

                                  <f:selectItems value="#{combo.origen}" />

                           <a4j:support event="onchange" reRender="destino" />

                     </rich:comboBox><br></br>

                     <rich:comboBox id="destino" value="${combo.idDestino}" directInputSuggestions="true" defaultLabel="Seleccione destino" width="219">

                        <f:selectItems value="#{combo.destino}"/>                                                       

                     </rich:comboBox>

package prueba;

import java.sql.CallableStatement;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.util.ArrayList;

import java.util.List;

import javax.faces.bean.ManagedBean;

import javax.faces.model.SelectItem;

import oracle.jdbc.internal.OracleTypes;

import dao.ConexionBDOracle;

@ManagedBean(name="combo")

public class TextBean {

          private String idOrigen;

          private String idDestino;

          private ArrayList<SelectItem> origen  = new ArrayList<SelectItem>();

          private ArrayList<SelectItem> destino = new ArrayList<SelectItem>();

          public List<SelectItem> getOrigen() {

                    Connection conexion             = null;

                    CallableStatement procedimiento = null;

                    ResultSet rs                    = null;

                    try{

                              conexion = ConexionBDOracle.GetConecction();

                              procedimiento = conexion.prepareCall("{ ?= call PASAJES.SP_BUSCA_ORIGEN_DESTINO(?,?) }");

                              procedimiento.registerOutParameter(1,OracleTypes.CURSOR);

                              procedimiento.setString(2, "");

                              procedimiento.setString(3, "1");

                              procedimiento.execute();

                              rs = (ResultSet) procedimiento.getObject(1);

                              while(rs.next()){

                                        origen.add(new SelectItem(rs.getString(2), rs.getString(1)));

                              }

                              procedimiento.close();

                              rs.close();

                              conexion.close();

                    }catch(Exception ex){

                              ex.printStackTrace();

                    }

                    return origen;

          }

          public List<SelectItem> getDestino() {

        System.out.println("idciudad: "+idOrigen);

                    Connection conexion = null;

                    CallableStatement procedimiento = null;

                    ResultSet rs = null;

                    try {

                              conexion = ConexionBDOracle.GetConecction();

                              procedimiento = conexion

                                                  .prepareCall("{ ?= call PASAJES.SP_BUSCA_ORIGEN_DESTINO(?,?) }");

                              procedimiento.registerOutParameter(1, OracleTypes.CURSOR);

                              procedimiento.setString(2, idOrigen);

                              procedimiento.setString(3, "2");

                              procedimiento.execute();

                              rs = (ResultSet) procedimiento.getObject(1);

                              while (rs.next()) {

                                        destino.add(new SelectItem(rs.getString(2), rs.getString(1)));

                              }

                              rs.close();

                              procedimiento.close();

                              conexion.close();

                    } catch (Exception e) {

                              // TODO Logear error

                              e.printStackTrace();

                    } finally {

                              try{

                                        if(conexion != null && !conexion.isClosed()){

                                                  if(rs != null)

                                                            rs.close();

                                                  if(procedimiento != null)

                                                            procedimiento.close();

                                                  conexion.close();

                                        }

                              }catch(SQLException ex){

                                        try {

                                                  conexion.close();

                                        } catch (Exception e) {

                                                  ex.printStackTrace();

                                        }

                                        // TODO Logear error de SQL

                                        ex.printStackTrace();

                              }

                    }

                    return destino;

          }

          public String getIdOrigen() {

                    return idOrigen;

          }

          public void setIdOrigen(String idOrigen) {

                    this.idOrigen = idOrigen;

          }

          public String getIdDestino() {

                    return idDestino;

          }

          public void setIdDestino(String idDestino) {

                    this.idDestino = idDestino;

          }

          public void setOrigen(ArrayList<SelectItem> origen) {

                    this.origen = origen;

          }

          public void setDestino(ArrayList<SelectItem> destino) {

                    this.destino = destino;

          }

}