> He attributes the ... algorithm... to an IBM publication
> (GC20-1707-0) "Identification Techniques"...is dated 1978, so  if
> you're a pack rat, you might have a copy in your manual library.
 
  Being pack rats ( :-) ) we found this manual, and it is a quite
  interesting manual.  I suggest that people interested in directory
  services and such find a copy somewhere and check through it.
  It's quite old, but our manual database claims that there was a
  revision (which I haven't found yet).  It talks about using
  various factors for recognising individuals, including things that
  don't apply to this discussion, like hair colour and so forth.
  None the less, interesting.
 
Michael