Hittade det här i dag på Macfixit
Terry Brady offers this mostly untested fix for enabling a default paper size other than US Letter. He writes:
"This hack appears to work for me, but there may be negative consequences that I haven´t yet determined. Essentially what I did was to delete the US Letter and US Legal page descriptions from this file:
´/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/
PrintCore.framework/Versions/A/Resources/PaperInfo.xml´
Editing the file requires invoking sudo from the command line.
Using PropertyListEditor (included with the Developer Tools), delete the first two ´com.apple.print.subTicket.paper_info_ticket´ objects (which correspond to US Letter and US Legal respectively) and then rename the subsequent ones so that they´re numbered from 1 to 4 instead of 3 to 6. Number 1 will now be A4."
En aningen krångligt,kanske???