(X)HTML5 schema downloader gets old broken files

[Blastoff]

In Emacs 24.3 (MacPorts) and nXhtml 2.09beta, after running the (X)HTML5 schema downloader via the menubar (nXhtml -> Tools -> Download/Update Schema Files), I attempted to open an XHTML5 file and get the error:
File mode specification error: (error "Reference to undefined pattern common.attrs.aria.role.tabpanel at position 2018 in ~/.emacs.d/rnc/html5/html5.rnc")

If I try to set the schema type manually to XHTML5 via the nXML menu ((XML -> Set Schema -> For Document Type -> XHTML5), the error is "nxml-display-file-parse-error: Reference to undefined pattern common.attrs.aria.role.tabpanel".
Google turns up zilch on these errors.

Upon inspecting the .rnc files, it looks like the applications.rnc included in html5.rnc references ARIA attributes in aria.rnc, but that file isn't included. Adding an include line for aria.rnc immediately before the applications.rnc line gets rid of the above errors, but now I get a new error:
Incorrect schema. Unknown datatype library http://whattf.org/datatype-draft

That link to the datatype-draft doesn't exist anymore. I get the feeling these .rnc files are pretty old.

A workaround is to replace the html5.rnc file with the one at https://raw.github.com/validator/schemas/gh-pages/html5.rnc

The (X)HTML5 schema downloader is really convenient, but it would be nice if nXhtml worked with the files that it grabs.