SMTP routing based on senders Domain

After a company split we have to seperate outgoing mail based on the sender’s Email Domain.

is it possible to do this with native domino or do we have to utilize some sort of MTA?

Subject: split

Not sure what you mean, are you trying to split outgoing SMTP mail to different servers? if the company’s sold, would it not be easier to move the users to a separate server then configure that server with a different route?