Using multiple IP Addresses

I would like Exim to use multiple IP addresses to send email from my discussion lists. I would like to use different IP addresses for each discussion list to isolate these lists.

I looked at the instructions for doing this and modified the cnf of Exim in WHM
I set OFF to send email from dedicated IP address
I set ON to reference /etc/mailhelo
I set ON to reference /etc/mailips

I wrote 3 files
mailhelo--
domain1.com: mx.domain1.com
domain2.com: mx.domain2.com
domain3.com: mx.domain3.com
domain4.com: mx.domain4.com

mailips
domain1.com: 192.1.2.1
domain2.com: 192.1.2.2
domain3.com: 192.1.2.3
domain4.com: 192.1.2.4

mail_reverse_dns
192.1.2.1: mx.domain1.com
192.1.2.2: mx.domain2.com
192.1.2.3: mx.domain3.com
192.1.2.4: mx.domain4.com

I can send mail to each of these IP addresses using the correct domain but all email sent by Exim comes from the dedicated IP address instead of the other three. I had assumed that if the mail came user@domain3.com and the email was sent to smtp IP mx.domain3.com, the email is sent out from 192.1.2.1 (mx.domain1.com)

I do not know what else to do to get this to work. I wanted this email to be sent out from 192.1.2.3 mx.domain3.com

 

Thank you for responding.
I am using DADAmail on a Bluehost dedicated server. I have setup DADAmail to send mail to SMTP and I have directed it to go to server mx.domain3.com and I also authenticate to that server. The email is coming from lista@domain3.com. The email is then sent out by Exim. When I examine the header of the email that is received using MXtoolbox analyze header tool, it appears that indeed the IP for domain3 did accept the email from dadamail but then it sent it out using the IP address of domain1.com which is the primary IP for the server.

If you want I can load the actual headers of such an email--obviously domain1.com domain3.com etc is not the actual domain names which will be displayed in the head in addition to the real IP address.

Thanks.
Michael