Problem showing and hiding element with JSF and Richfaces

Question

I am trying to use a selectOneRadio, when performing an exchange action should show an element and disappear if it was another option, however, there is no exchange.

        ***<h:panelGrid columns="1">
            <h:form id="planetsForm">
                <h:selectOneRadio value="#{atendimentoSinistroBean.location}"
                    style="width:40%">
                    <f:selectItem itemLabel="One" itemValue="1" />
                    <f:selectItem itemLabel="Two" itemValue="2" />
                    <f:selectItem itemLabel="Three" itemValue="3" />
                    <a4j:support event="onchange" reRender="cId" update="@form" />
                </h:selectOneRadio>

                <rich:calendar id="cId"
                    rendered="#{atendimentoSinistroBean.location==2}" />
            </h:form>
        </h:panelGrid>

    </rich:panel>***