I have an ISPConfig 3 setup on Centos 6.3. I am using all of the features including mail on the domains setup but one. One of them is using a secondary mail server (inside the lan, but different server) I have configured the DNS settings with an A - Record for mail pointing to the ip address and an MX - record for mail.example.com, but it is still trying to deliver it on the ISPconfig machine.
I'm lost at this point. I don't know what I could of missed. Anyone who might be able to shed some light on the topic would be greatly appreciated.
P.S. - The external mail server is a Kolab 3 mail server inside the same lan that I a using for testing right now.