Project Managment Calendar

I want to use as a project management tool, BUT the calendar does not support time slots for events. It only allows an event for 1 hour but in real life this never fits. Either it is too short or too long. So whats the use exactly to implement a time functionality to the calendar and then not allow defining how long the event takes???
I saw that a couple of guys already requested this for years. Is it really such a difficult feature???