Raymond Mercier suggested... > http://wwwold.dkuug.dk/jtc1/sc2/wg2/docs/n2422.pdf
And these 6 Sogdian letters were accepted and do appear in Unicode 4.0. > http://www.gengo.l.u-tokyo.ac.jp/~hkum/pdf/SIE3.pdf That documnet is apparently in some non-standard encoding and the French accented letters don't show up properly. Rick