Eastern Yiddish, is one of the two varieties of Yiddish that have been recognised as languages in their own right in the ISO-639-3 (ydd). in OmegaWiki, we now have our first 213 Expressions in this language and I am impressed with the amount of work that has gone into it; most have annotations indicating hyphenation and the pronunciation using IPA notation.
Eastern Yiddish is not one of the languages supported by MediaWiki, and the mechanism for showing localised content is connected to the language selected in the "User Preferences". I have been given some help from Siebrand what files need to be changed and added. Kim helped me with doing it for the first time and now the first localisation is visible for Eastern Yiddish.
The MediaWiki localisation itself uses Yiddish as the fall back language so the experience is pretty good for now. What Siebrand indicated is that is is possible to include languages like Eastern Yiddish in the BetaWiki. This would create stubs that are of benefit to OmegaWiki. It would prepare for the moment when people start localising in earnest.
I think it would be a good thing, but I am interested to learn what other people think.