Outlook: Run code when a calendar entry is added or updated?

I currently have some VBA code that runs through and modifies all my calendar entries. I'd like to no longer run this as a batch process.

Is there an API hook that will tell me when a calendar entry is added or modified so that I can run it against a single calendar entry开发者_开发问答 on-demand rather then having to periodically run it against all entries?

You might like to look at the application level event, ItemAdd : http://msdn.microsoft.com/en-us/library/aa155701(v=office.10).aspx#odc_ch11olevents_topic6