> >This is not true for any C++ code.
> 
> What makes you think that?

I was thinking of argument propagation rules and assignement implicit 
conversions (when function pointers and pointers to member functions
are involved) where NULL would have slightly less strict rules (which is
why g++ implements it as __null) - but I can't find an example where "0"
does not work right now.

So maybe I'm wrong.

Martin