Как добавить дополнительное поле в VirtueMart 2.0 в форму "Задайте вопрос по этому товару"? - [VM2&3] Дизайн, оформление

<form method="post" class="form-validate" action="<?php echo JRoute::_('index.php?option=com_virtuemart&view=productdetails&virtuemart_product_id='.$this->product->virtuemart_product_id.'&virtuemart_category_id='.$this->product->virtuemart_category_id.'&tmpl=component') ; ?>" name="askform" id="askform">

         <label><?php echo JText::_('COM_VIRTUEMART_USER_FORM_NAME')  ?> : <input type="text" class="validate[required,minSize[4],maxSize[64]], namefields, .ask-a-question-view"  value="<?php echo $this->user->name ?>" name="name" id="name" size="30"  validation="required name"/></label>
         <br /><br />
         <label><?php echo JText::_('COM_VIRTUEMART_USER_FORM_EMAIL')  ?> : <input type="text" class="validate[required,custom[email]]" value="<?php echo $this->user->email ?>" name="email" id="email" size="30"  validation="required email"/></label>
         <br/><br />
         <label>
            <?php
            $ask_comment = JText::sprintf('COM_VIRTUEMART_ASK_COMMENT', $min, $max);
            echo $ask_comment;
            ?>
            <br />
            <textarea title="<?php echo $ask_comment ?>" class="validate[required,minSize[<?php echo $min ?>],maxSize[<?php echo $max ?>]] field" id="comment" name="comment" rows="5"></textarea>
         </label>
         <div class="submit" style="margin-top:20px; ">
            <input class="button" type="submit" name="submit_ask" title="<?php echo JText::_('COM_VIRTUEMART_ASK_SUBMIT')  ?>" value="<?php echo JText::_('COM_VIRTUEMART_ASK_SUBMIT')  ?>" />

            <div class="width50 floatright right paddingtop">
               <?php echo JText::_('COM_VIRTUEMART_ASK_COUNT')  ?>
               <input type="text" value="0" size="4" class="counter" id="counter" name="counter" maxlength="4" readonly="readonly" />
            </div>
         </div>

         <input type="hidden" name="virtuemart_product_id" value="<?php echo JRequest::getInt('virtuemart_product_id',0); ?>" />
         <input type="hidden" name="tmpl" value="component" />
         <input type="hidden" name="view" value="productdetails" />
         <input type="hidden" name="option" value="com_virtuemart" />
         <input type="hidden" name="virtuemart_category_id" value="<?php echo JRequest::getInt('virtuemart_category_id'); ?>" />
         <input type="hidden" name="task" value="mailAskquestion" />
         <?php echo JHTML::_( 'form.token' ); ?>
         
      </form>