Spec draft 05

I think I've addressed all the issues that were assigned to me 
(including Martin's corrections to the examples and Jeff Bohren's 
comments during the most recent conference call).  If I've missed 
something or failed to address an issue satisfactorily, please let me 
know. 

I've attached spec draft 5 and the current list of open issues.
(I have, but have not attached, a complete list of spec issues addressed 
in this draft.  I'll send this list to anyone who wants one.)