>The IESG can move a document to "Historic" status.  Generally, that's 
>done by an RFC explaining why.  I don't know of any attempt to do that 
>to 2228, and I probably would if one were pending.
>unused Proposed Standards.  Whether or not the IETF should undertake 
>the consider effort necessary to clean these up is debatable.

FWIW, RFC 2228 is fairly well-known in the Kerberos community; I use a
RFC 2228 ftp client every day.  I'm not sure how widely it is used outside
of the Kerberos community, though (the implementations that I'm aware
of that do GSSAPI are only really set up to do Kerberos/GSSAPI ... but
there might be some DCE implementations out there that I'm not aware of).

--Ken