There is a latin9.def at http://www.loria.fr/~gustedt/iso8859-15.html
which allows one to use iso8859-15 screen fonts and simply go
\usepackage[latin9]{inputenc}. It works fine.
I noticed that Lyx doesn't offer support for latin9. Since latin9
a.k.a iso8859-15 includes the euro sign as well as OE and oe
ligatures, it comes in handy for a lot of European users. Please
consider supporting it in the next release.
FYI: I'm not subscribed to this list, please CC me on replies.
--
Philipp Lehman <[EMAIL PROTECTED]>