Disposing object instances

[psto@xs4all.nl (Peter Stone)]

Does anybody know how to mark an object as garbage, other than removing
all references to it?

This is needed when you want to free memory from objects that contain 
references to other objects. If you do nothing to this object hierarchy 
(gc) thinks it is still alive since its elements are referenced.

I noticed I have to remove all references of all objects that I don't need,
otherwise memory runs out. Is there other way to inform the gc directly 
that somehing is not needed anymore? Something similar like 
dispose-subviews? 

Peter Stone
psto@xs4all.nl