Hi again, I am attaching a new version of the patch, with some typos fixed and a explanatory note in the commit message on the choice of the character U+201C as Greek second-level opening quotes. In case anyone is interested in what Yanis Haralambous answered me in a recent mail, I reproduce here (with his permission) a fragment of the message: #+begin_quote [...] to answer your question, the average Greek writer would use U+201C. For those that seek Greek typographic tradition, there should be a substitution [...], but it would be more appropriate to do it on the glyph level. From a grapholinguistic point of view there is absolutely no need of using U+201F, the difference should be on the alllographic level, the grapheme should only carry the information "CLOSING DOUBLE SECOND-LEVEL QUOTATION MARK" and U+201C is a good choice for representing that grapheme since it is used in most countries of the world… #+end_quote Therefore, if someone wishes to use the historical character [in a LuaTeX or XeTeX document] (represented by U+201F), I agree with Yannis that it is better to use that symbol at the glyph level and not at the character level. For this scenario a GSUB opentype feature would work very well, since it is a historical character (as in the case of historical ligatures, alternate glyphs, etc.). Best regards, Juan Manuel