All our web apps fail because the html element lacks a lang attribute. I guess we need to set it to "en" even when we provide localization messages?? I'm not sure how it could be reset dynamically. In this case, hard-coding it to "en" should be okay. (This will have to be done in ResponseBean and StatusBean too, of course.)
The rsvp app fails the color contrast analyzer – red type provides insufficient contrast unless the size is 18 pt or above, according to the error message. We can use Oracle red in images, but not in text. (We're going to have to fix our doc landing pages because of this, too.)
The data tables lack a summary. The h:dataTable element has a summary attribute that we'll need to use in index.xhtml; you can add the summary attribute directly in the bean code.
Every table gets errors about missing row headers. I think we need scope attributes like those in http://www.w3schools.com/tags/att_td_scope.asp, or alternatively we can use id and headers attributes.
The text field in the form must have a label with a for attribute. If you don't want the label visible on the page, you need to use css style attributes.