Schema files are supposed to change very rarely, most of the times when new items are added, seldom when something is modified (e.g. when a flaw in some standard track, or as a consequence of some ietf clarification, details of an existing schema change), while in principle no deletion should ever occur.
--Quanah
-- Quanah Gibson-Mount Principal Software Developer ITSS/Shared Services Stanford University GnuPG Public Key: http://www.stanford.edu/~quanah/pgp.html
"These censorship operations against schools and libraries are stronger than ever in the present religio-political climate. They often focus on fantasy and sf books, which foster that deadly enemy to bigotry and blind faith, the imagination." -- Ursula K. Le Guin