TCVN, Telex, and VNI keyboard layouts for Mac OS X from version 10.2 that emit Vietnamese text in Unicode Normalization Form C (NFC), where the entire vowel including the intonation mark is represented by a single code point. The TCVN layout is functional on Mac OS X 10.2; Telex and VNI require version 10.3, codename “Panther”.
http://www.ils.uec.ac.jp/~herr/Vietnamese-1.2.dmg
