[NNTP] Article number wording

[Russ Allbery]

To have something more concrete to talk about, here's what I think several
people are asking for.  Note that I still haven't been convinced this is
the right thing to do, particularly now, but it's easier to discuss the
proposal when there's text to look at.

    arrive earlier.  The server SHOULD allocate the next sequential
    unused number to each new article.
 
-   Article numbers MUST lie between 1 and 4,294,967,295 inclusive.  The
-   client and server MAY use leading zeroes in specifying article
-   numbers, but MUST NOT use more than 16 digits.  In some situations,
-   the value zero replaces an article number to show some special
-   situation.
+   Article numbers MUST be positive integers.  The client and server
+   MAY use leading zeroes in specifying article numbers.  In some
+   situations, the value zero replaces an article number to show some
+   special situation.
+
+   This standard imposes no maximum limit on article numbers other than
+   the maximum length of an NNTP command.  Implementors are encouraged
+   to support arbitrarily large article numbers and SHOULD use at least
+   the largest integer type their software can support.  However, note
+   that many widely deployed NNTP clients cannot handle article numbers
+   larger than 2,147,483,647 or 4,294,967,295 and article numbers higher
+   than that are likely to cause interoperability problems.
 
 6.1.  Group and article selection

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>