Here comes the unit test instructions. (My bad! I should have attached
this with the PATCH)

0. Apply the previous patch

1. Open the attached hand-created test.odt file in archive mode (Note:
   .odt files are zip files)

2. You are likely to see a bunch of xml file as shown below.

--8<---------------cut here---------------start------------->8---
M Filemode      Length  Date         Time      File
- ----------  --------  -----------  --------  -----------------------
  [snip]
  -rw-rw-rw-      3008  19-Jun-2011  13:07:44  content.xml
  -rw-rw-rw-       532  19-Jun-2011  13:07:44  manifest.rdf
  -rw-rw-rw-     11100  19-Jun-2011  13:07:44  styles.xml
  -rw-rw-rw-      1127  19-Jun-2011  13:07:44  meta.xml
  [snip]
  -rwx------      8855  19-Jun-2011  18:40:04  settings.xml
  -rw-rw-rw-      1989  19-Jun-2011  13:07:44  META-INF/manifest.xml
- ----------  --------  -----------  --------  -----------------------
--8<---------------cut here---------------end--------------->8---

3. Visit those xml files in nxml-mode
4. Make sure auto-validation is on.

--8<---------------cut here---------------start------------->8---
(eval-after-load 'rng-nxml
  '(setq rng-nxml-auto-validate-flag t))
--8<---------------cut here---------------end--------------->8---

5. Use C-c C-s C-w or M-x rng-what-schema and ensure that the right
schemas are picked up for validation.

--8<---------------cut here---------------start------------->8---
Using schema c:/Program Files/emacs-24.0.50/etc/schema/OpenDocument-v1.2-cs01-schema.Using schema c:/Program Files/emacs-24.0.50/etc/schema/OpenDocument-v1.2-cs01-manifest-schema.rnc
--8<---------------cut here---------------end--------------->8---

6. Use C-c C-n or M-x rng-next-error and  ensure that things are OK.
   - Currently manifest.xml reports 

--8<---------------cut here---------------start------------->8---
      Missing attribute "manifest:version"
--8<---------------cut here---------------end--------------->8---