If the file named “META-INF/manifest.xml” contains a element whose manifest:full-path attribute has the value "/", then a "mimetype" file shall exist, and the content of the “mimetype” file shall be equal to the value of the manifest:media-type attribute 4.16.10 of that element.
The validator currently fails to check that these are consistent as stated.
Section 3.3 of the OpenDocument 1.3 specification, part 2 for packages states:
The validator currently fails to check that these are consistent as stated.