SPF softfail for forwarded emails to Gmail account

I've been able to make SPF pass on all the sent emails from my Postfix server. But for forwarded domains which simply redirect email to my gmail id I see softfail in the SPF.

For example if I send email from a hotmail account to contactus@workingwoman.org then it is forwarded to test email id ragraggupta8899@gmail.com.

I've added SPF header "spf1 a mx -all" for my hostname(host.tariffplans.com) as well for all domains. The A record of all domains/subdomains is correctly pointing to my server IP : 23.239.30.81

But in the forwarded email header .. Google shows it as softfail. What could be the problem?:

Delivered-To: rag.raggupta8899@gmail.com
Received: by 10.114.96.70 with SMTP id dq6csp51447ldb;
        Sat, 19 Jul 2014 23:05:03 -0700 (PDT)
X-Received: by 10.182.65.66 with SMTP id v2mr22896624obs.74.1405836302184;
        Sat, 19 Jul 2014 23:05:02 -0700 (PDT)
Return-Path: 
Received: from host.tariffplans.com (tariffplans.com. [23.239.30.81])
        by mx.google.com with ESMTPS id js4si25593503obc.98.2014.07.19.23.05.01
        for 
        (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128);
        Sat, 19 Jul 2014 23:05:02 -0700 (PDT)
Received-SPF: softfail (google.com: domain of transitioning bhasker@hotmail.com does not designate 23.239.30.81 as permitted sender) client-ip=23.239.30.81;
Authentication-Results: mx.google.com;
       spf=softfail (google.com: domain of transitioning bhasker@hotmail.com does not designate 23.239.30.81 as permitted sender) smtp.mail=bhasker@hotmail.com
Received: from BLU004-OMC4S20.hotmail.com (blu004-omc4s20.hotmail.com [65.55.111.159])
    (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits))
    (No client certificate requested)
    by host.tariffplans.com (Postfix) with ESMTPS id 668E01E1619
    for ; Sun, 20 Jul 2014 11:35:01 +0530 (IST)
Received: from BLU181-W79 ([65.55.111.136]) by BLU004-OMC4S20.hotmail.com with Microsoft SMTPSVC(7.5.7601.22712);
     Sat, 19 Jul 2014 23:05:01 -0700
X-TMN: [mcaEHqstvkaYJBg7Y5zPleq+hEPF4BC7]
X-Originating-Email: [bhasker@hotmail.com]
Message-ID: 
Content-Type: multipart/alternative;
    boundary="_dfcd1b0c-5d39-4204-a29c-16fb51556946_"
From: Bhasker Yamsani 
To: "contactus@workingwoman.org" 
Subject: testing
Date: Sun, 20 Jul 2014 02:05:00 -0400
Importance: Normal
MIME-Version: 1.0
X-OriginalArrivalTime: 20 Jul 2014 06:05:01.0018 (UTC) FILETIME=[8A96E3A0:01CFA3E0]