RE: koma letter template?

[Beyer, Marcus]

Marcus Beyer > > Is there a template for letter(koma-script) available?
Herbert Voss > can't you use g-brief-german?

Using that template I get an error about an unknown text class
"Das Dokument verwendet die unbekannte Textklasse 'g-brief-de'".
Where can I get this class?
I am using the winport of LyX1.1.6fix1 with MiKTeX 1.2.
Is this class included in a newer Version of MiKTeX?

Marcus