I am getting this fail message, using the plugin in v.2.8.4 in a custom layout with WordPress as a CMS. Layout validates both xhtml-strict and css, but I don't know how to test the mobile plugin's theme markup... do these messages relate to the MOBILE theme's markup, doctype, etc?

Your page does not use XHTML Mobile Profile

XHTML-MP should be used as the default markup for your pages. Use of XHTML-MP ensures that your pages will work on the widest variety of mobile devices as well as on desktop browsers. The following graph shows how XHTML-MP is supported by the overwhelming majority of mobile browsers.

FAIL
Does not validate against XHTML Basic 1.1
FAIL
Does not validate against XHTML Mobile Profile 1.2
WARN
Does not validate against its stated doctype