Completed tasks should disappear, right?

[Empty Headed Terry]

Just got a new Palm Treo 755 and I think I'll like it but one thing. When I complete a task in one of my contextual lists the little box is checked off but it stays. I have so many tasks it can be difficult but when the completed ones won't go away it becomes overwhelming.

Someone please tell me how to get them to disappear when completed like tasks do in outlook.

Thanks in advance,
Terry