I highly doubt that you have a virus on entourage. It's more likely that someone is sending email from their account, with your return address, effectively spoofing. Then you recieve the bounced emails that you never sent. I cannot find any reports of a Entourage virus on OS X.
John A
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I to am having that problem, do you know how I can stop the spoofing?
You can't really. The spammer's servers can append any email address they choose, so you don't have any control. However, you can send a polite email to the servers that are bouncing the mail asking them to stop it - as you're not really sending them. Usually the return addresses from the firewalls/servers are no-reply, so you'll often have to visit their website to get the webmaster's email address.
Hope this helps
John A
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