Problem sending mail

UNIX AIX
1

Everytime i try sending mails using the command line have a reply form the daemon saying :

? 1
Message 1:
From MAILER-DAEMON Wed Apr 25 10:42:36 2007
Date: Wed, 25 Apr 2007 10:42:36 -0500
From: Mail Delivery Subsystem <MAILER-DAEMON>
To: malarie
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
boundary="KAA31348.1177515756/vinson.processia.com"
Subject: Returned mail: Service unavailable
Auto-Submitted: auto-generated (failure)

This is a MIME-encapsulated message

--KAA31348.1177515756/vinson.processia.com

The original message was received at Wed, 25 Apr 2007 10:42:36 -0500
from malarie@localhost

----- The following addresses had permanent fatal errors -----
malarie@processia.com

--- The transcript of the session follows ---
... while talking to smtp.globetrotter.net.:
>>> MAIL From:<malarie@vinson.processia.com>
<<< 550 5.1.8 invalid/host-not-in-DNS return address not allowed
554 malarie@processia.com... Service unavailable

--KAA31348.1177515756/vinson.processia.com
Content-Type: message/delivery-status

Reporting-MTA: dns; vinson.processia.com
Arrival-Date: Wed, 25 Apr 2007 10:42:36 -0500

Final-Recipient: RFC822; malarie@processia.com
Action: failed
Status: 5.0.0
Remote-MTA: DNS; smtp.globetrotter.net
Diagnostic-Code: SMTP; 550 5.1.8 invalid/host-not-in-DNS return address not allo
wed
Last-Attempt-Date: Wed, 25 Apr 2007 10:42:36 -0500

--KAA31348.1177515756/vinson.processia.com
Content-Type: message/rfc822

Return-Path: <malarie>
Received: (from malarie@localhost)
by vinson.processia.com (AIX4.3/8.9.3/8.9.3) id KAA28252
for malarie@processia.com; Wed, 25 Apr 2007 10:42:36 -0500
Date: Wed, 25 Apr 2007 10:42:36 -0500
From: malarie
Message-Id: <200704251542.KAA28252@vinson.processia.com>
To: malarie@processia.com
Subject: testing

--KAA31348.1177515756/vinson.processia.com--

Any ideas??

We changed our registrar last week, I think this is causing some problems.
I was using NS61.WORLDNIC.COM and since we are now hostin our website with bluhost, i had to change to NS1.BLUEHOST.COM but i still have the same ISP...