I agree on that one, ok ok we should not compare, wonder what M$ does.
I think in CB it only get's cleaned just before a new compile starts.
[EDIT] : is probably an easy one to implement, I would suggest Michael creates a patch for this. Since his bird is flying high now he's now also writing patches.
Compiler (plug-in?) will need extra function, since that's the who knows which page it is in the message manager that should be cleared, or something like that, have been in that code some months ago ....