Help Exchange Calendar Sync

[htech]

A user just got a moto droid (most of our users have Eris). I setup a connection to our Exchange server and it only gave me options to sync email and contacts. Everything is syncing fine but I noticed the calendar is empty. I checked the gmail account and it shows calendar syncing so I'm wondering after reading a couple posts that the phone only supports one calendar. Verizon pre set this phone up with the gmail syncing the calendar. The user wants our exchange calendar. Do I just uncheck the gmail calendar sync option? then have to re-enter the exchange account so it realizes no calendar is installed? not sure what I need to do to switch the calendar from gmail sync to exchange sync. thanks!