Win Srv 2003 failover/cluster

How would I go about setting up 2 servers in a hot standby/failover scenario running exchange and files. This is actually Windows 2003 Server however no 2k3 forum is available to post.
Scenario is I want to run exchange and fiule share from 1 server however if this server fails I cant afford any downtime so I need an automated swapover which must contain all the upto date data.