Um...that's one of the things I know exists but don't know where to find.
It's probably available from the IETF or IANA sites (a.k.a. www.isi.edu,
I believe). The standards-track one is big, hairy, and *really* slow. It
only took a year to get PNG done (well, not counting the delay in actually
getting a number assigned); the standards one can drag on much longer than
that, apparently.
Greg