Need help with Contact Us form - Joomla! Forum - community, help and support

i thought should easy one, guess i'm wrong. must doing wrong. when fill out contact form in beez 5 , send failure notice, says:

hi. qmail-send program @ blah.com.
i'm afraid wasn't able deliver message following addresses.
this permanent error; i've given up. sorry didn't work out.

<email@email.com>:
74.208.5.90 not recipient.
remote host said: 550 5.1.1 <email@email.com>... user unknown {mx-us007}
giving on 74.208.5.90.

--- below line copy of message.

return-path: <myemail>
received: (qmail 19494 invoked uid 5084); 14 dec 2012 01:11:32 -0000
to: email@email.com
subject: sales: test 3
x-php-script: www.mysite.com/index.php/contact-us 70.104.149.77
date: thu, 13 dec 2012 20:11:32 -0500
from: website's email address
reply-to: tom <my personal email>
message-id: <81948be6cc3403a3585e4b2fe64708b9@www.mysite.com>
x-priority: 3
x-mailer: phpmailer 5.2.1 (http://code.google.com/a/apache-extras.org/p/phpmailer/)
mime-version: 1.0
content-transfer-encoding: 8bit
content-type: text/plain; charset="utf-8"

this enquiry email via http://www.mysite.com/ from:
tom <tom@myhomeemail.com>

here's config in global settings:

mailer stmp
from email: email
from name: name
sendmail path: /usr/sbin/sendmail
smtp authentication: no
smtp security: none
smtp port 587
smtp username
smtp password
smtp host

i don't know deal is. anyone?? email@email.com strange.

figured out. had use contact manager make changes. duh!