Quoting Mike Kercher mike@CamaroSS.net:
Probably a silly question, but did you rebuild your sendmail.cf after modifying the sendmail.mc?
Yes, I did rebuilt it, and I did restarted sendmail.
I also attempted to add 'a' flag to the TLSMTA (found advice on comp.mail.sendmail). It didn't helped of course (per documentation, it simply requires authentication, so after adding it, all commands were failing).
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