Can someone clarify exactly what is the correct mime type syntax to use?

At the URL--> http://mobiforge.com/testing/story/fixit-mime-types
It states to use .htaccess (if you have one, which I do) and include the line:
# XHTML
AddType application/xhtml+xml .xhtml

Done That.

However, after running my site via mobiReady again.

I still have a RedFlag stating "Incorrect or missing MIME types were detected"

The Recommendation is below:
"For XHTML-MP, the recommended MIME type is application/vnd.wap.xhtml+xml or application/xhtml+xml. Unlike HTML, XHTML-MP should not be served as text/html."

Please clarify which is the correct syntax and is .htaccess the right place to put the mime type declaration?

Specially if, I'm using Wordpress with your recent dotMobi WordPress Mobile Pack.

Thanks in advance for your response.

Best,

Spicer