Thread:Project:Support desk/MediaWiki 1.16.5 Doesn't Validate

MediaWiki 1.15.3 was XHTML 1.0 Transitional and had no errors. I use the HTML Validator add-on for Firefox and for MediaWiki 1.16.5 it doesn't show if it has errors or not, it just says "HTML 5 - see Page Source"

MediaWiki 1.16.5 seems to use XHTML 1.0 Strict. It doesn't validate. It has 11 errors.

How can I get MediaWiki to use the proper doc type so it will validate?