Guóyǔ (國語) as prerequisite to citizenship

Mark Swofford's Pinyin News reflects on a Taipei Times report regarding a proposed language requirement for foreign nationals wishing to become Taiwan (R.O.C.--so far) citizens. The Times article refers to "a basic grasp of Mandarin," but when Swofford checked with the Ministry of the Interior, he was told other Taiwan languages (Hakka, Minnan, and possibly Aboriginal languages) would be acceptable alternatives. Swofford comments,

I suspect some of the ambiguity may lie in how Guóyǔ (國語) is translated. Most of the time the word refers to Mandarin. Recently, however, the government has occasionally chosen to translate Guóyǔ not as "national language" (i.e. Mandarin) but "national languages" (i.e. the more than one dozen languages of Taiwan: Mandarin, Taiwanese, Hakka, and the languages of Taiwan's tribes).