Enable / Disable DatePicker of JSF in Portal

<h:inputText id="txtDate"  value="#{pc_MyBean.startDt}" >

    <f:convertDateTime pattern="dd-MM-yyyy" />

    <hx:inputHelperDatePicker firstDay="1" />

</h:inputText>

1) Enable this in portal

    document.getElementById('view'+'<portlet:namespace/>'+':frmName:txtDate').disabled = false;

    hX_5.getComponentById('view'+'<portlet:namespace/>'+':frmName:txtDate').redraw();

1) Disable this in portal

    document.getElementById('view'+'<portlet:namespace/>'+':frmName:txtDate').disabled = true;

    hX_5.getComponentById('view'+'<portlet:namespace/>'+':frmName:txtDate').redraw();