I'm very sorry, I didn't make it clear last time. The following is the related code:

</ul>
<ul class="shipping_textarea">
<textarea name="comments" cols="45" rows="3" class="txt_review_cont" onblur='if(this.value == "") this.className="txt_review_cont"' onfocus='this.className=""' style="OVERFLOW:auto;border:1px #ccc solid;height:80px;width:540px;"></textarea> </ul>

you can aslo refer the bottom of this page (product review part). The two pages have the same text area. And someone has told me that it is a kind of image, but i can't find the URL.

Looking forward to your help! Thanks!