Consensus Call on Latin Sharp S and Greek Final Sigma

Alexander Mayrhofer alexander.mayrhofer at
Mon Nov 30 09:57:39 CET 2009

(2) Both characters should be DISALLOWED

(Disclaimer: I am not at all an expert of greek grammar, but i consider
those two cases similar..)

Defining them PVALID creates changes to deployed namespace. This allows
for ambigiuity (even after the transition), given that clients may
implement any mapping of their choice. This ambigiuity in turn greatly
reduces the usefulness of those characters in registrations - the effort
for introducing bundling (and explaining to users that their domain
names might or might not work) is in no relation to the gained

Besides that, use of Latin Small Letter Sharp S has been significantly
reduced by changes to German grammar in 1996/2004/2006, and it's use has
been completely abolished in Switzerland in 2006. 


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