Larry, where does gnome-print grab this info?

It looks like this is coming straight from the ppd here, but changes are stored in the gnome_print_condfig settings appropriately, if no ppd exists for the settings that are automatically created are for USLetter but I think the problem in this case is the initial ppd.  Matthias what does the ppd file in /etc/cups/ppd/ for your printer list as the DefaultPageSize?

All PPDs I have set A4 as the DefaultPageSize, as I routinely check this after installing a new printer (these are in fact only for three printers -- not all applications support CUPS instances):

$ grep DefaultPageSize /etc/cups/ppd/*.ppd
/etc/cups/ppd/bjgp.ppd:*DefaultPageSize: A4
/etc/cups/ppd/bjtp.ppd:*DefaultPageSize: A4
/etc/cups/ppd/hpgimp.ppd:*DefaultPageSize: A4
/etc/cups/ppd/ljdraft.ppd:*DefaultPageSize: A4
/etc/cups/ppd/lp.ppd:*DefaultPageSize: A4
/etc/cups/ppd/r220.ppd:*DefaultPageSize:A4

Matthias, how did you add the printers initially?  Were they created durring the install with yast or at a later date with some other tool?

More data: I created a new printer with yast and opened in evolution and the paper defaulted to a4 in both the ppd and evolution.  Second I created a new printer of the same type with gnome-cups-add and the paper defaulted to letter.  I'll dig deeper into the gnome-cups-add code, but it is doubtful this bug has anything to do with evolution.

Larry, I do not recall exactly, and since I bought this printer in December 2005, I appear to not have relevant logs any longer either.

It was either YaST's printer module or the CUPS web interface <http://localhost:631/>, or perhaps (but less likely) CUPS's lpadmin command. It was definitely not a GNOME or KDE tool.

If this info isn't sufficient, let me know and I'll try to see if there are differences in the default page (paper) size WRT the tool used to configure the printer.

If I remember correctly (at least some versions ago) gtklp
always stored user-specific default values for all print queues
in the user's ~/.lpoptions file, see
http://en.opensuse.org/SDB:Print_Settings_with_CUPS
for background information about lpoptions files
and which default values are used for a print job.

Matthias,
please attach both your user's ~/.lpoptions file (if exist)
and the system /etc/lpoptions file (if exist).

In general a printing frontend should ony store defaults into ~/.lpoptions
if there was an explicite user request to do it (e.g. after the user
clicked a button like [save settings] or something like this).
It should not happen that the user changes the settings for one
particular print job and then this settings are made the defaults
for all subsequent print jobs.

System default /etc/cups/lpoptions from one host (there's a user account with a verbatim copy of these options in $HOME/.lpotions, and other accounts without any .lpoptions):

Default lp HPOption_Tray2=True ManualFeed=False InputSlot=Tray2 Resolution=1200x1200dpi HPOption_Tray3=False HPEconoMode=False HPOption_PaperPolicy=NearestSizeNoAdjust Smoothing=Off

System default /etc/cups/lpoptions from another host:

Default lp HPOption_Tray2=True ManualFeed=False InputSlot=Tray2 Resolution=1200x1200dpi HPOption_Tray3=False HPEconoMode=False HPOption_PaperPolicy=NearestSizeNoAdjust Smoothing=Off

User lpoptions on the latter are (relevant line is "lp"):

Dest bjgp StpColorPrecision=Best StpDitherAlgorithm=HybridEvenTone
Dest ljdraft Smoothing=On
Dest ljdraft/ljdraft1p Duplex=None
Dest lp _kde-filters=true Collate=True
Dest lp/lp1p Duplex=None _kde-filters=true Smoothing=On

I wonder is this is related to bug 148707

Comment #3 shows that the page zize is right in the PPDs.
Comment #8 doesn't show any page size setting.
Therefore it still seems that Evolution/gnome-print produce PostScript
with a wrong page size setting.

Matthias,
can you print into a file from Evolution and attach it
so that we can see which PostScript Evolution/gnome-print produce.

No response in several months.  Please reopen if you are able to provide the requested information.