EventHandlers Firing Events

I ran into a pretty bizzare behavior in SSIS:

I am trying to set up a package with a built-in auditing. It has a OnPreExecute, OnPostExecute and OnError event handlers. I am trying to record when the package starts, completes, and the completion status. Each one of these event handlers has a script task that does the logging. I put in debug message boxes into each event handler script to understand what goes on. So here's the sequence of events:

1. When starting the package the OnPreExecute event fires. Right away it fires the second time. I'm guessing what happens here is the script task within the event handler fires its own OnPreExecute event - that's how the first message really pops up. The second message is generated by the actual package-level OnPreExecute event.

2. I have a condition within the OnPreExecute event handler which might set the task status to failure. You would expect the OnError handler to fire, right?.. Wrong! The package dies without firing either OnError or OnPostExecute event....

3. If i remove the condition in step 2, and force an error in the package body, i get an OnError event, and then 2 OnPostExecute events ( i guess for the same reason as in step 1).

What I'm trying to understand is why in the world my OnPreExecute and OnPostExecute events get fired by their own event handlers, yet when i fire other events within these event handlers the appropriate (other) event handler does not run.

Any ideas will be greatly appreciated.