[exim] Change IP for different senders

Hi
Is it possible to send email from different IP, depending on email address ?

Example :
I have a domain : domain.com

If message is sent by user1@???, I want to use IP aaa.aaa.aaa.aaa
If message is sent by user2@???, I want to use IP aaa.aaa.aaa.bbb

Is it possible ?
And how to do this ?

Thanks for your help

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