Can I be identified as spammer?

[kerber]

Hello everybody,

I'm using Zimbra as Relay to Exchange in the same network.

My sent e-mails are going with this header:

Received: from mx.facilitynet.com.br (webmail.facilitynet.com.br [200.184.165.46])




These hostname differences can identify my server as spammer ?


Guys, i'm worried!
Thanks in advance,

Daniel



Details:

mx.facilitynet.com.br is the hostname of relay
webmail.facilitynet.com.br is the reverse of 200.184.165.46.

[uxbod]

Why do you think it would identify you as a spammer ? Have you appeared on any RBLs because of it ?

[kerber]

Testresult for 200.184.165.46:

This IP IS CURRENTLY LISTED in our Database.
Please note that this listing does not mean you are a spammer, it means your mailsystem is either poorly configured or it is using abusive techniques.
If you don't know what BACKSCATTER or Sender Callouts are, click the links above to get clue how to stop that kind of abuse.


To track down what happened investigate your smtplogs near 31.01.2010 22:20 CET +/-10 minutes.

You will either find that your system tried to send bounces or autoresponders to claimed but in reality faked senders, or your system tried sender verify callouts against our members near that time.

So you should look for outgoing emails that have a NULL SENDER or POSTMASTER in MAIL FROM and which got rejected at remote systems.

Read the rejection texts carefully and it shouldn't be a big deal to figure out what caused or renewed your listing.


History:30.01.2010 21:50 CET listed

A total of 3 Impacts were detected during this listing. Last was 31.01.2010 22:20 CET +/- 10 minutes.
Earliest date this IP can expire is 28.02.2010 22:20 CET.



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I'm listed at backscatterer.org with the message above.

How can I fix it these null senders?

[uxbod]

Have you looked through /var/log/zimbra.log as the backscatter.org message has indicated ?