And again, welcome back.
The XHTML standard states that XHTML documents SHOULD be sent as application/xhtml+xml, but most people still use text/html. For XHTML 1.0, this is listed as a MAY, as in, you MAY do this, For versions beyond, such as XHTML 1.1, it states that the data SHOULD NOT be sent as text/html. It does state that it SHOULD be sent as application/xhtml+xml.
If there is any questions, or if you need some assistance applying this code, please feel free to leave a comment.
