Mail clustering

Hi Everyone,

I have recently created a mail cluster in order to make some tests. I have changed the mail server into a standalone mail server, I had the message saying that my mail server was the last one on the cluster and now I can't recreate a cluster the option is not disponible, I'd like to know where are located the config files of the cluster in order to be able to recreate a cluster. I'm not really familiar with Mac OS X server (comming from Windows and exchange ) but i'm working on it. I'd also like to know if it is possible to create multiple configuration files for mail server to have the possibility to change server if one server fail ( in the case I choose not to make a cluster).
The configuration I have is 2 Xserve and a san (Promise). The servers are running Leopard and i have an Xsan.
The first server is an OD and a mail server the second one is an OD replica.
So my options are either a mail cluster (which i can't recreate as there is traces of the old one) or a non active mail server on the second server with configuration files to start it if needed (if the first server fail).