JSF+datatable+Hibernate

Hi all,
I'm tryint to display the rows of a table usign JSF framework, but I
receive the following error

javax.faces.el.EvaluationException: javax.faces.FacesException:
javax.faces.FacesException: Can't instantiate class:
'ar.com.redlink.MarWebSucursales.AdministradorUsuariosBean'.. class
ar.com.redlink.MarWebSucursales.AdministradorUsuariosBean :
java.lang.IllegalAccessException: Class java.beans.Beans can not
access a member of class
ar.com.redlink.MarWebSucursales.AdministradorUsuariosBean with
modifiers ""

I'm new working on this platform, so I need your help!!!

Here is the back bean class

public class AdministradorUsuariosBean {
    private List listaUsuarios = new ArrayList();

    public List getListaUsuarios() {
        return cargarListaUsuarios();
    }

    public void setListaUsuarios( List listaUsuarios ) {
        this.listaUsuarios = listaUsuarios;
    }

    private List cargarListaUsuarios() {
            Session session=HibernateSessionFactory.getSession();
            if( session != null ) {
                String SQL_QUERY = "FROM TUsuarios u " +
                                    "ORDER BY u.NombreUsuario";

                Query query = session.createQuery(SQL_QUERY);
                listaUsuarios = query.list();
            }

The jsp code is this
   <f:view>
        <h:dataTable value="#{admUsuarios.listaUsuarios}" var="usuario">
            <f:facet name="header">
                <h:outputText value="Lista de usuarios"/>
            </f:facet>
            <h:column>
                <f:facet name="NombreUsuario">
                    <h:outputText value="Nombre de Usuario"/>
                </f:facet>
                <h:outputText value="#{usuario.nombreUsuario}"/>
            </h:column>

and the faces-config.xml is this
    <managed-bean>
      <description>Administrador de usuarios</description>
      <managed-bean-name>admUsuarios</managed-bean-name> <managed-bean-
class>ar.com.redlink.MarWebSucursales.AdministradorUsuariosBean</
managed-bean-class>
      <managed-bean-scope>session</managed-bean-scope>
    </managed-bean>

What I'm doing wrong?
Thanks in advance!!!