Hi Jean-Marc, thanx for your quick answer. Ok, it's not possible to tell lyx which layout i want to use, mayby i can replace the system default with my layout. Which one is the default, i found thee *.ist files gglo.ist, gind.ist and nomencl.ist. They are all located in "/usr/share/texmf/makeindex". I'm the only user (and root) of this machine, so nobody else will be angry.
-- Mit freundlichem Gruss Yours sincerely Roland Schmitz