Spamassassin RDNS_NONE matches, but there is a RDNS

I got a a little problem – spam assassin's RDNS_NONE-rule matches on my outgoing mails but there is a RDNS set for all hosts, that are in the delivery-chain.

If I send an Email to "receipient-forwarding-address@example.com" which gets redirected to another account, I get the following header:

Return-Path: <receipient@example.com>
Delivered-To: receipient@mailserver.example.com
Received: from localhost (localhost [127.0.0.1])
    by mailserver.example.com (Postfix) with ESMTP id 3CD4D1D237A1
    for <receipient@example.com>; Fri, 17 Apr 2015 14:53:03 +0200 (CEST)
X-Virus-Scanned: amavisd-new at example.com
Received: from mailserver.example.com ([127.0.0.1])
    by localhost (mailserver.example.com [127.0.0.1]) (amavisd-new, port 10024)
    with ESMTP id oUIr35qsq6dA for <receipient@example.com>;
    Fri, 17 Apr 2015 14:53:03 +0200 (CEST)
Received: from closed-relay.outgoing-mailserver.com (closed-relay.outgoing-mailserver.com [123.123.123.123])
    by mailserver.example.com (Postfix) with ESMTP id DEC0B1D23794
    for <receipient@example.com>; Fri, 17 Apr 2015 14:53:02 +0200 (CEST)
Received: from localhost (localhost [127.0.0.1])
    by closed-relay.outgoing-mailserver.com (Postfix) with ESMTP id 52E3844379B
    for <receipient@example.com>; Fri, 17 Apr 2015 14:52:53 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at closed-relay.outgoing-mailserver.com
Received: from closed-relay.outgoing-mailserver.com ([127.0.0.1])
    by localhost (closed-relay.outgoing-mailserver.com [127.0.0.1]) (amavisd-new, port 10024)
    with ESMTP id MFFwpRFp8aZy for <receipient@example.com>;
    Fri, 17 Apr 2015 14:52:51 +0200 (CEST)
Received: from outgoingantispam.outgoing-mailserver.com (outgoingantispam.outgoing-mailserver.com [1.1.1.1])
    by closed-relay.outgoing-mailserver.com (Postfix) with ESMTPSA id 3DB4E443794
    for <receipient@example.com>; Fri, 17 Apr 2015 14:52:51 +0200 (CEST)
Received: from my.webhosting-server.com (unknown [2.2.2.2])
    (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits))
    (No client certificate requested)
    by outgoingantispam.outgoing-mailserver.com (Postfix) with ESMTPS id A7DB3182E6E
    for <receipient@example.com>; Fri, 17 Apr 2015 14:52:48 +0200 (CEST)
Received: by my.webhosting-server.com (Postfix, from userid 30)
    id 6D9E128223E; Fri, 17 Apr 2015 14:52:48 +0200 (CEST)
X-Original-To: receipient-forwarding-address@example.com
Delivered-To: receipient-forwarding-address@example.com
Received: from mailserver.example.com (mailserver.example.com [80.147.42.111])
 by my.webhosting-server.com (Postfix) with ESMTPS id 355FE281888
 for <receipient-forwarding-address@example.com>; Fri, 17 Apr 2015 14:52:48 +0200 (CEST)
Received: from localhost (localhost [127.0.0.1])
 by mailserver.example.com (Postfix) with ESMTP id A2E7E1D23786
 for <receipient-forwarding-address@example.com>; Fri, 17 Apr 2015 14:52:47 +0200 (CEST)
X-Virus-Scanned: amavisd-new at example.com
Received: from mailserver.example.com ([127.0.0.1])
 by localhost (mailserver.example.com [127.0.0.1]) (amavisd-new, port 10024)
 with ESMTP id xwhW2ZM2tq8D for <receipient-forwarding-address@example.com>;
 Fri, 17 Apr 2015 14:52:47 +0200 (CEST)
Received: from [10.18.163.218] (ersc145.goemobile.de [134.76.38.145])
 by mailserver.example.com (Postfix) with ESMTPSA id DF8D01D23770
 for <receipient-forwarding-address@example.com>; Fri, 17 Apr 2015 14:52:46 +0200 (CEST)
From: Test <receipient@example.com>
Content-Type: multipart/alternative;
 boundary="Apple-Mail=_4A11EFC1-C1A0-443C-A838-95B3BBBD3921"
Subject: Test
Message-Id: <93E953CD-A9A7-4DDE-B7E1-A09BAC115231@example.com>
Date: Fri, 17 Apr 2015 14:52:53 +0200
To: Test <receipient-forwarding-address@example.com>
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2098\))
X-Mailer: Apple Mail (2.2098)
X-PPP-Message-ID: <20150417125248.13139.91108@my.webhosting-server.com>
X-PPP-Vhost: provider.com
X-Provider-MailScanner-EFA-Information: Please contact postmaster@provider.com for more information
X-Provider-MailScanner-EFA-ID: A7DB3182E6E.ABCF8
X-Provider-MailScanner-EFA: Found to be clean
X-Provider-MailScanner-EFA-From: receipient@example.com
X-Provider-MailScanner-EFA-Watermark: 1429879971.81756@AJtdCMx5yR0wKblR1j2VGA