Yes that change is in the code I sent to Ernst. Other than making it easy to add "Notes" or "All day" events, it also simplifies the code and makes the form less confusing.

Examples of how the duration dropdown makes life easier:

•  It is impossible for the end datetime be before the start datetime.
• You can set the default event duration for a calendar so usually they only have to set the start datetime.
• A small JavaScript displays the end datetime in long format after they select a duration so that they can see exacty when an event ends, same as before.
• The existing form has TWO end dates. One for when the event ends and one for when recurrence ends. This is very confusing to users. The duration dropdown eliminates that confusion. The only time you need an end date is when your event occurs on more then one day.

Questons welcome.