Minor tweaks to ffi addendum

[Simon Marlow]

>    In fact, I
>    always considered it something of a mistake to rely on automatic
>    finalizers to do anything with human visible consequences (though
>    I seem to remember that Self or Smalltalk relied on this for
>    closing windows and found it very effective).

Ah yes - if you consider that one instance of "human visible
consequences" is "not running out of memory", then I agree :-)

Cheers,
	Simon