Append HTTP Status Codes to XML

Hi,

I am in the middle of putting a RESTful api together for a new app.

I was wondering if anyone has any suggestions or experience with adding
a status code to all xml output?

So that a response that looks like
<user>
  <about_me>this is a test descripton of me new line test</about_me>
</user>

Will look like
<response code=”200”>
    <user>
        <about_me>this is a test descripton of me new line
test</about_me>
    </user>
</response>

Or maybe something similar to how twitter have implemented error codes,
any suggestions?
(
http://groups.google.com/group/twitter-development-talk/web/api-documentation
)

Thanks,
Scott