I'm in the middle of trying to set up an email solution using Postfix on FC1 too. I was getting all ready to install Postfix from scratch, and overwrite the default sendmail installation, when I spotted people talking about this 'redhat-switch-mail'. So I've used that to switch over to Postfix, and it seems to be working.
However, I was wondering what exactly redhat-switch-mail does when it switches from sendmail to Postfix (or the other way around!). While it's great that we have utilities like redhat-switch-mail, I'm always a bit wary of relying on graphical programs and not really understanding what's going on under the hood. So, just to satisfy my curiosity, what would I have to do to 'switch' from sendmail to Postfix manually at the command line?
Specifically: what config files need to be changed to switch between MTAs? Something in xinetd so that the correct mail programs are invoked? What else? And what does redhat-switch-mail do with the sendmail binaries? Does it just back-up the sendmail versions and overwrite them with the Postfix versions, or does it do something more sophisticated?
Yes, I'm a newbie.