I don't believe so unless they are enabled by default. It also depends on your core. If it's ArcEMU then there are sql's queries that enable + spawn and disables + despawns.
If you're using Trinitycore then you just enable through the DB game event, check here for details http://collab.kpsn.org/display/tc/Game+event+tc2
They should be automatic. I remember logging in to my local server not long ago and a event was going on. If no events are starting, perhaps you don't have them enabled.