Relaying config for sendmail for multiple domains

[cybex77]

I am very new to Sendmail and I am trying to configure it to relay for multiple domains but forward then to specific IP addresses without the use of DNS. As an example if mail comes in for anyuser@testdomain.com sendmail will forward all email for testdomain.com to 192.168.1.4 but if email for test2domain.com comes into the system it forwards that to 10.0.0.10.

I am not sure how to configure this and would appreciate any help that someone could give me please.

Thanks in advance.