Version: (using KDE KDE 3.5.1) Currently, the Content-transfer-encoding of outgoing mails (or "Message property" in KMail's terminology) is a "Common option" --- common for all "Outgoing account". I'd need to set it differently for different outgoing accounts, and I think it is also more logical that way.
It makes sense, but it puts a greater burden on KMail because it may have to re-encode the email before transmitting. That means the email has to be stored in pure 8-bit and unsigned in the Outbox folder and must be signed only when it's about to be delivered -- when the outgoing server is known. If you have a server that is broken WRT 8-bit MIME, set to Quoted Printable for all accounts and it should work.
Thank you for your feature request. Kmail1 is currently unmaintained so we are closing all wishes. Please feel free to reopen a feature request for Kmail2 if it has not already been implemented. Thank you for your understanding.
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