64-bit sequences

Hello, newbie here.  I need 64-bit sequences.  I started looking at
sequence.h, sequence.c, and some other files, and I have some questions
before I start mucking up your code.  :-)  (I'd rather do it right and
contribute something to the pgsql project.)

But first, has this issue come up in the past, and was a decision made to
keep sequences simple as an "int4" type only?  Please clue me in on the
history.  Is there any reason not to push forward with "int8" sequences,
as some sort of compile-time or run-time option?


Paul Caskey
New Mexico Software
paul@nmxs.com