Email server for Fedora

Everyone seems to have their own preference - mine is Postfix. There is a nice howto for installing it on CentOS; I imagine this translates to Fedora without too much difficulty. If you do not need POP/IMAP access, skip the part about installing Dovecot.

You should also look into setting up Postfix restrictions and greylisting to reduce spam. Be aware that using block lists (rejectrblclient) can result in false positives. pbl.spamhaus.org is quite conservative; if it isn't enough, zen.spamhaus.org is a bit broader. The bl.spamcop.net list is in their words "aggressive" so may not be a good choice. I personally run a mailserver without a block list at all - greylisting and the Postfix sanity checks do a very good job on their own.