ps2pdf: landscape in PDF

[Reiner Elmers]

Hello!

It's the first time I visit this newsgroup, so please be patient
if my question has been answered 1042 times already.

When I try to convert a Postscript document which is in landscape
orientation using ps2pdf, I always get a PDF file where the document
is rotated to portrait orientation (page size A4).

Is there any possibility (e.g. a GS command line option) to tell
ps2pdf that it should produce a PDF file which is displayed in
landscape orientation when opened with the Acrobat Reader?

Thanks for answering,

Reiner