Michael Everson will probably also answer, but yes, he knows what you are talking about.
The problem here is in part the result of too easily using the term "letter" here. These things are really a Bengali orthographic solution to the problem of representing vowel sounds (in borrowed words) that are alien to the "slots" of the basic phonology, and which don't have obvious representations using the basic vowel letters of the system. As Michael suggested, the solution makes use of an existing conjunct form of ya, in combination with other vowel forms, and then provides a reading for them. In principle, at some point in the future, either the phonology or the orthography or both could evolve to the point where the entire constructs start to get handled as basic orthographic units (or "letters") for Bengali, but it isn't really the place of the Unicode Standard to try to push that evolution, if there is a well-defined way to represent the sequence using the characters already in the standard. In some respect, the problem is similar to arbitrary orthographic adaptation that people using the English alphabetic subset of the Latin script sometimes make when attempting to represent sounds in other languages that have no standard representation with English spelling rules. An example which comes to mind is using "kl'" to try to represent a lateral affricate, for example. The fact that the lateral affricate might be a phonological unit in the other language, and that it might even have a unitary letter representation (e.g., U+019A barred-l) in some other orthography, doesn't mean that if people start to represent it "kl'" in the "English alphabet" that we then have to turn around and encode a "kl'" character in Unicode. --Ken > I said: > ? (I am talking about the letters > > mentioned in the Unicode Indic FAQ, > > http://www.unicode.org/faq/indic.html#13) > > Just to be clear, I mean the letters called 'Vowel_A_zophola_AA' & > 'Vowel_E_zophola_AA' as mentioned in the above mentioned FAQ. > > Andy
