If you're in Germany, simply go to a DB ticket office or call DB at 030-2970.

You can see availability on www.trenitalia.com (but not book pass reservations).

Thank you, think I will just do that.

Another question; I see that some train schedules are not available yet on Trenitilalia (I assume that has to do with the change of the schedule for next year?). However, we want to take the night train from Salerno to Syracuse and for the 23 December it is not available yet. However, the train shows going through Rome. Is it possible to make a reservation from Rome and get in Salerno?

Currently the only train showing on Trenitalia for 23 Dec is the 2300 night train that does not stop in Salerno, but there are connections from Salerno to Rome showing.

Exactly. The new timetable starts on 11 December and Trenitalia's new timetable is not complete yet. Especially night trains are available quite late each timetable change.

There are 2 night trains from Rome to Siracusa, an early one and a late one. The late one is already shown in the timetable but is full on 23 December, according to trenitalia.com. The early one does not show yet in the timetable but it is the only one you can board in Salerno.

I see. Is there any information when the second night train or its timetable will becoem available?

Unfortunately not. Whenever Trenitalia feels like it :(