Sieve vacation using null sender

[Andre Nathan]

Hello

I'm setting up sieve vacation, and while it is working, the vacation
messages are sent using the null sender on the envelope "mail from".
I'm using cyrus 2.1.15. Below are the test script and the relevant
postfix logs:

if header :contains "from" "<andre.nathanNOSPAM at .gmail.com>" { 
  vacation :addresses "andre at NOSPAM.digirati.com.br" :subject "Vacation test"
    "Vacation test";
}

Oct  8 14:52:56 cesio postfix/smtpd[5373]: E1C376008D: client=neptunio.k8.com.br[200.185.109.90]
Oct  8 14:52:56 cesio postfix/cleanup[5374]: E1C376008D: message-id=<cmu-sieve-13666-1097257976-0 at neptunio.k8.com.br>
Oct  8 14:52:56 cesio postfix/nqmgr[18922]: E1C376008D: from=<>, size=769, nrcpt=1 (queue active)
Oct  8 14:54:14 cesio postfix/smtp[5376]: E1C376008D: to=<andre.nathanNOSPAM at gmail.com>, relay=gsmtp171.google.com[64.233.171.27], delay=78, status=sent (250 OK 1097258054)

Is there any way to set the envelope from to a real address?

Best regards,
Andre
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