Apple iPad iOS 4.2 - Manual (Page 81)

Alerts
Set calendar alerts: In Settings, choose General > Sounds, then turn Calendar Alerts
on. If Calendar Alerts is off when an event occurs, iPad displays a message but makes
no sound.
Sound alerts for invitations: In Settings, choose “Mail, Contacts, Calendar.” Under
Calendars, tap New Invitation Alert to turn it on.
81 Chapter 9 Calendar