On 07/01/2014 02:40 PM, Andrew Cunningham wrote:
> It is not possible to construct a language tag for current ALA-LC Arabic
> romanisation scheme, since there is no appropriate subtag registered. A
> language tag ar-Latn ... is insufficient since there are many widely
> different romanisation schemes for Arabic, and the language tag does not
> have enough specificity
Sure there is, using private use tags.