Postfix setup informations

Hi

On a virtualmin vps i have hostname server.domain1.com and i’m using postfix to send mails out (like newsletter etc). Email mx server for receiving are elsewhere.
When the site domain2.com (virtual server) send an email, this is always "mailed-by server.domain1.com.
What should i change in postfix to make domain2.com to be the author of this email?

Currently results:
From: test@domain2.com
mailed-by: server.domain1.com
signed-by: domain2.com (this is dkim i have setup)

wished results:
From test@domain2.com
mailed-by: domain2.com
signed-by: domain2.com

Is it possible?

/subscribing as I need to know the same.

Hi.

I’ve never seen “Mailed-by:” from postfix. Something else must be inserting that.