calendar primefaces

<h:outputLabel value="Ingrese Fecha Inicial" for="finicial"/>
<p:calendar id="finicial" value="#{nacidoVivoRenaviController.FInicial}" pattern="dd/MM/yyyy"   locale="es"     required="true" onkeypress="return permite(event, 'none')" requiredMessage="Fecha Inicial Requerida" navigator="true" effect="fadeIn" effectDuration="100">
        <p:ajax event="dateSelect" update="ffinal" />
 </p:calendar>
<h:outputLabel value="Ingrese Fecha Final" for="ffinal"/>
<p:calendar id="ffinal" value="#{nacidoVivoRenaviController.FFinal}" mindate="#{nacidoVivoRenaviController.FInicial}" pattern="dd/MM/yyyy"  locale="es" required="true" onkeypress="return permite(event, 'none')" requiredMessage="Fecha Final Requerida" navigator="true" effect="fadeIn" effectDuration="100">
         <f:attribute name="finicial" value="#{nacidoVivoRenaviController.FInicial}"/>
         <f:validator validatorId="primeDateRangeValidator" />
</p:calendar>