MS Exchange for Calendar/Scheduling ONLY

My school district moved away from MS Exchange several years ago due to viruses. We now use Centrinity’s FirstClass (FC) Client/Server. To USE FC’s interface, you must login. Many of our admin’s would like to “take” their schedules/appt’s with them but FC does not provide portability as an Outlook or a Palm desktop client would. Can MS Exchange be used JUST as a Calendar/Scheduling application OR MUST it’s email functionality be enabled? Our environment is Win2000 Active Directory and Mac OS9/X. Outlook & Entourage, coupled with an Exchange server would be a very useful addition, minus the email (and possible virual infection that comes along with it). Thank you!