While it's true that you cannot capture or override programmatic execution
of commands (i.e. a script calling send on a message object).you can capture
and override the user interface execution of commands (the user pressing the
send button).
To have your add-in called when a UI command is executed, do the following:
* Retrieve the command bar that contains the button the you want to
override.
* Call the command bar's Find method. It will return a command button
object.
* Setup and event sink with the command button.
* When your event sink method is called be sure to set the cancelled
parameter to true
This works for standard buttons. I haven't been able to get this to work
with the drop-down buttons (i.e. new mail item button).
