Many thanks, especially to Carl and Dennis for their contributions! Thomas J. Kraus -- Dr. Thomas J. Kraus tj.kraus at gmx.de (groups) t.j.kraus at web.de (private) Amberger Str. 2c 92318 Neumarkt Telef. +49 91 81 46 25 14 Mobile +49 17 05 82 11 62