These apply to iPhone 2.0 or 3G - versions that have Exchange support.
Settings - Mail Contacts Calendars - Add Account - Exchange
Email - enter your address
Domain - HCI
username & password (no "HCI\" needed in front of username)
(Unable to verify certificate? - Accept)
Server - hci-webmail.hci.utah.edu
(change other parameters as desired - eg, replace default signature, choose to sync Contacts, etc.)