End Date should be greater than Start Date using CJuiDatePicker

<?php 
echo $form->labelEx($model, 'start_date');
$this->widget('zii.widgets.jui.CJuiDatePicker', array(
'model' => $model,
'htmlOptions' => array(
'size' => '10', // textField size
'maxlength' => '10', // textField maxlength
'class' => "input-small"
),
'options' => array(
'showAnim' => 'fold',
'dateFormat' => 'yy-mm-dd',
'changeMonth' => true,
'changeYear' => true,
'yearRange' => '2000:2099',
'onSelect' => 'js:function( selectedDate ) {
    // #end_date is the ID of end_date input text field
    $("#end_date").datepicker( "option", "minDate", selectedDate );
     }',
    ),
));

echo $form->labelEx($model, 'end_date');            
$this->widget('zii.widgets.jui.CJuiDatePicker', array(
'model' => $model,
'htmlOptions' => array(
'size' => '10', // textField size
'maxlength' => '10', // textField maxlength                        
'class' => "input-small"
),
'options' => array(
'showAnim' => 'fold',
'dateFormat' => 'yy-mm-dd',
'changeMonth' => true,
'changeYear' => true,
),
));
            
?>