r-t-l writing style

one of the outcomes of the ODF plugfest was an issue with handling right-to-left
writing styles of languages.

ODF 1.1, 15.5.36 Writing Mode lists the possible options, but doesn't define a
default value (some applications apparently guess the writing style based upon
the language, but this assumes that a Consumer would know the writing
style of each and every language the Producer might come up with)

The non-normative Appendix F. Bidirectional (BiDi) Scripts might also provide
some insights..