[Plugin: FormBuilder] Localhost on MAC—How on earth is it successfully sending emails?

My wife has set up MAMP on our mac, and is developing a website locally.

She recently installed FORMBUILDER, and is having trouble receiving emails on the domain she has set up. I have a hunch this is because we dont have EMAIL set up correctly on the LOCALHOST, and the formbuilder has no idea how to send an email properly. The “From” addresses are not valid, and I think our domain server just rejects them. I have a hunch that GMAIL and YAHOO are okay with them, and thats why we receive them on those accounts.

My question is……HOW ON EARTH can formbuilder successfully send emails when it has no knowledge of any email server? In other words, what server is used to send the actual email?

As you can see in the email header I received below—its somehow using my LOCAL IMAC setting to send the email. (Which make NO SENSE) I dont have any SMTP services set up!!! I am MYSTIFIED how an actual email gets sent out successfully.

Thanks for any insight on what may be going on.

–gerry

From gameandrea@hotmail.com Thu May 24 14:48:06 2012
X-Apparently-To: xxxx@yahoo.com via xx.xx.xx.xx; Thu, 24 May 2012 14:48:08 -0700
Return-Path: <xxxxxx@dads-imac.local>
Received-SPF: none (domain of dads-imac.local does not designate permitted sender hosts)
Authentication-Results: mta1294.mail.bf1.yahoo.com from=hotmail.com; domainkeys=neutral (no sig); from=hotmail.com; dkim=neutral (no sig)
Received: from 127.0.0.1 (EHLO Dads-iMAC.local) (xx.xx.xx.xx)
by mta1294.mail.bf1.yahoo.com with SMTP; Thu, 24 May 2012 14:48:08 -0700
Received: by Dads-iMAC.local (Postfix, from userid 502)
id 18B267AABD2; Thu, 24 May 2012 17:48:06 -0400 (EDT)
To:
Subject: Contact Form
From: gameandrea@hotmail.com
Reply-To: gameandrea@hotmail.com
Content-Type: text/plain; charset=”UTF-8″
Message-Id: <20120524214807.18B267AABD2@Dads-iMAC.local>
Date: Thu, 24 May 2012 17:48:06 -0400 (EDT)
Content-Length: 192

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