[cups.general] Letter instead of A4 after install via Point'n'Print

[Kay Obermueller]

Hello everyone,
according (hopefully) to these howtos I have setup printers and prepared
their cups postscript drivers to be installed automatically via Samba and
the so called Point'n'Print method:

https://forums.gentoo.org/viewtopic-t-456501-highlight-.html
http://www.linuxprinting.org/kpfeifle/SambaPrintHOWTO/Samba-HOWTO-Collection-3.0-PrintingChapter-11th-draft.html

Everything works pretty well except that a new windows client that
installs the driver tries to print out as Letter instead of A4. I can then
change this setting and it is correctly saved, but only on this particular
client. Is there a way to set this beforehand in the driver on the server?
In smb.conf this is set:
default devmode = Yes
Does this have influence on this issue?
Just this "little" problem needs to be solved then this Cups server works
_perfectly_. Who has an idea and would like to help me?

Kay