Tengwar?

Apart from the fact that that extension hasn't been ratified yet, Tengwar is like Arabic in that considerably more glyphs are needed to display it than to represent it -- you need extra glyphs for characters with combining diacritics, not least because two or more diacritics can apply to the same character (e.g. U+E00C U+E040 U+E045 U+E05C is one glyph). The work involved in generating those glyphs, or in putting enough intelligence into the font engine to construct those glyphs on-the-fly, isn't likely to appear on Sonicblue's product roadmap any time soon :-(

Peter