Can the <machine-word> class be a subclass of <abstract-integer>? The documentation says only that it is a subclass of <object>, but given that odd?, even?, zero?, positive?, negative?, \= , \<, min and max are defined on <machine-word> it makes sense that it ought to fit into the existing numeric heirarchy. Cheers, -Peter S. Housel- housel@acm.org http://members.home.com/housel/