how to get rid of sendmail X-Authentication-Warning?

[Andy Spiegl <debian-user.andy@spiegl.de>]

Hi!

I've been searching the docs and the list archives, but I just can't find
out why my sendmail (8.11.4+8.12.0.Beta12-4 and 8.12.1-2) still produce the

 X-Authentication-Warning: hamster.int.radiomaranon.org.pe: spiegl set sender to Andy@spiegl.de using -f

/etc/mail/sendmail.mc contains:
 define(`confPRIVACY_FLAGS', `needmailhelo,novrfy,noexpn,noreceipts,noverb')dnl

Somewhere I read that "authwarnings" is on per default, but it didn't say
how to turn it off.

/etc/mail/trusted-users contains:
 mail
 root
 spiegl

Please help.  I'd appreciate any hint or pointer.
 Andy.

-- 
 Dr. Andy Spiegl, Radio Marañón, Jaén, Perú
 E-Mail: Andy@spiegl.de, Andy@radiomaranon.org.pe
 URL: http://spiegl.de, http://radiomaranon.org.pe
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