Andre Engels wrote:
In general, we have gone with ISO-639 in deciding what is a language and what a dialect, only Allemanish and Aromanian have been accepted without such a code. However, that too is not an official policy, just a "the way we have done it till now".
And it is worth noting in this context that deference to ISO codes was primarily done as a convenience, to avoid having to have a lot of complex arguments inside the community. The thought was that the ISO codes are defined by a neutral, standard body, and that we could just defer to their judgment.
As it turns out, in my opinion, the ISO codes are only really "correct" for the major languages. In terms of the question of dialect vs. language, they are highly politicized and quite often wrong.
--Jimbo