NOTE: This method is called only if you
implemented IwodPop3Notify interface in your application,
and wodPop3Server1.Notification
property has received reference to
instance of your implementation.
This notification method is called after user issues
'LIST' command to list messages on the server. This
notification is informational only, so you can store
information about this locally in case you need it. For
instance, you might want to check if user is aware he has
email or not.