An explanation of this behavior is located in the post announcing the new beta release:
viewtopic.php?f=5&t=697#p3307The changelog is another good place to start when you notice new behavior. It's located at the same location you download PT.
For betas:
http://ota.versatilemonkey.com/beta/For official releases:
http://ota.versatilemonkey.com/beta/Podtrapper now has a notification profile for when an episode finishes downloading. The notification system for PT works the same way as your phone/messaging/reminder notifications, by using a notification profile.
Blackberry has a common notification system that all programs can use. To modify its behavior, go to Profiles -> Advanced..., highlight the profile you want to change, Menu -> Edit -> PodTrapper Podcast Downloaded. Note that there are different profiles [Loud, Vibrate, Quiet, Normal, etc.]. You should check to see that PT's behavior is what you desire under each profile. You can modify the notification behavior for any other app in that list.