How to multihome: How do I prevent mail server from listening on one IP address

I’m trying to switch from Mac OS X Server’s mail server to Kerio, on the same machine. I’ve added another IP address to the machine, and set Kerio to only listen on that IP address. However, the bloody Mac OS X Server’s mail server listens on both IP addresses.

Does anyone know how to prevent cyrus and postfix and any other service that has to do with mail from latching onto all available IP addresses?

Thanks,

Adam