The Lite edition doesn't have a client-side (JavaScript) API. You can handle the EventClick event using JavaScript but you will need to invoke the delete command manually using custom PostBack call or using jQuery:
EventClickHandling="JavaScript"
EventClickJavaScript="if (confirm('Delete?') { __doPostBack('ctl00$ContentPlaceHolder1$DayPilotScheduler1','PK:{0}') }"