Secure my centos Plesk unix server from spammer ? !

Avg Bid (USD)
Project Budget (USD)
$30 - $250

Project Description:
I am worried someone has installed a script on my server, I have changed the root password but it seems to have not helped

I get the messages

Hi. This is the qmail-send program at
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

<>: failed after I sent the message.
Remote host said: 554 delivery error: dd This user doesn't have a account () [0] -

--- Below this line is a copy of the message.

Return-Path: <>
Received: (qmail 17839 invoked by uid 0); 13 Jan 2011 09:33:48 +0000
Date: 13 Jan 2011 09:33:48 +0000
Message-ID: <>

etc etc

In my mail box, It seems someone using my server to send spam.

I will also need a version of cacti totally removed and perhaps a free server scanner or similar if one is available to scan in future for such trojans, scripts etc

Skills required:
Computer Security, Script Install, System Admin, UNIX, Web Security
Hire Preorders
Project posted by:
Preorders United Kingdom
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