Text Area size?

Hey,

I’m trying to reduce the text area size of my text area box.. I have read the FAQs and they didn’t seem to work.. have a look:
<p>Your Feedback Message
[textarea your-message 10×10 ] </p>

Why doesn’t this change the size of the column and width to 10×10?
Have i done it wrong?

Can someone amend this for me,

Thanks!

http://ww.wp.xz.cn/extend/plugins/contact-form-7/