It took me ages to figure this out so I’ll post it here in case (a) it can be of help to someone else who has the same problem and (b) I might be able to find it again if I have to do it again and can’t remember how.
Anyway, I need to configure Kleopatra to send PGP signed mail with a v3 signature. The flag to use on the command line would normally be:
–force-v3-sigs.
So how to configure this in Kleopatra?
Turned out to be easy in the end:
Find gpg.conf which for me was in C:\Documents and Settings\user\Application Data\gnupg
Add the following to the last line of the file (ie after the bit that says it will not not change anything below these lines):
force-v3-sig
Note: don’t use the dashes as you would with the command line flag - that was the bit that took me a while to figure out.
Save the file and that’s it.
I guess the procedure would be similar to edit other things in the gpg.conf file.