Mailer-daemon FROM address change?

[fishnyc22]

Hey everyone. I have a question.

I have 3 domains on my server running 8.0.1.

mydomain1.com
mydomain2.com
mydomain3.com

When qmail trys to send a message to a fake address, i get an email from qmail saying the following...

The problem is that the script that sent the message was from mydomain3.com. Is there a way to have the mailer-daemon message come from mydomain3.com NOT mydomain1.com?
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From: [email protected]

Hi. This is the qmail-send program at founditfirst.com.
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.

<[email protected]>:
Sorry, I couldn't find any host named p.com. (#5.1.2)
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Thanks for the help.

Fish
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