org.apache.jackrabbit.rmi.client.ClientNode cannot be cast to net.fortuna.ical4j.model.Component - I didn't see anywhere in the servlet code that you are casting ClientNode to Componet. So the error might be coming from different code section. Can you share the line no. indicated in the error log at which the cast is failing.
subject: ClassCastException while reading ics file with ical4j in JackRabit