sentora sending mails from IPV6?

[wallmapu]

Hi.

I am having spam issues as Gmail and Yahoo label my mails as spam. The strange thining is, gmail receives my mails from the ipv6 address of my server. these are the headers (addresses slightly modified for safety):

Code:

Delivered-To: boxer123@gmail.com
Received: by 10.31.82.70 with SMTP id g67csp1773004vkb;
        Mon, 27 Jul 2015 23:39:36 -0700 (PDT)
X-Received: by 10.194.221.71 with SMTP id qc7mr62430511wjc.9.1438065575556;
        Mon, 27 Jul 2015 23:39:35 -0700 (PDT)
Return-Path: <roberto@example.com>
Received: from panel.example.com ([2a00:d879:6:345::85b9])
        by mx.google.com with ESMTP id eu6si35207072wjc.80.2015.07.27.23.39.33
        for <boxer123@gmail.com>;
        Mon, 27 Jul 2015 23:39:34 -0700 (PDT)
Received-SPF: softfail (google.com: domain of transitioning roberto@example.com does not designate 2a00:d879:6:345::85b9 as permitted sender) client-ip=2a00:d879:6:345::85b9;
Authentication-Results: mx.google.com;
       spf=softfail (google.com: domain of transitioning roberto@example.com does not designate 2a00:d879:6:345::85b9 as permitted sender) smtp.mail=roberto@example.com;
       dkim=pass header.i=@example.com;
       dmarc=pass (p=NONE dis=NONE) header.from=example.com
Received: from panel.example.com (localhost [IPv6:::1])
by panel.example.com (Postfix) with ESMTPA id E5A3F22B4F
for <boxer123@gmail.com>; Tue, 28 Jul 2015 03:39:20 -0300 (CLT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=example.com; s=mail;
t=1438065560; bh=0CqfS5HVjYWlo5wiB39H1oCVQ3ePnPAlFcMPVtZTyRY=;
h=Date:From:To:Subject;
b=IgfnZjRpMHf91F0HMctpKnAIiZiZ25N1aCU1z0RZ9jCHUUz+ofLX0eFA2PcB4gO7l
zsl2bIZ+iQlfCI8+ZetTbFAd4nOkLyrNM6iv0wk7+XrMcZKgwFtnE1qi2z+dZkyct0
DkO0ryrqNTb38CM6yrfbCn0fQZsUUUFzFqtjWZGY=
MIME-Version: 1.0
Content-Type: multipart/alternative;
 boundary="=_6fb01acd5e56948d1499d72219e4c3fa"
Date: Tue, 28 Jul 2015 03:39:20 -0300
From: Roberto Matus <roberto@example.com>
To: boxer123@gmail.com
Subject: google
Message-ID: <3bc9c8aa2ce21dec50b3c19639845e32@example.com>
X-Sender: roberto@example.com
User-Agent: Roundcube Webmail/1.0.4

--=_6fb01acd5e56948d1499d72219e4c3fa
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset=US-ASCII

I guess I have to ad that ipv6 address to the spf entry, am i right? However, why is it using the ipv6 at all? where can i control/modify that?

[Me.B]

Do you have any IPV6 setup there?