IDN with Gemini?

[Stephane Bortzmeyer]

The specification
<gemini://gemini.circumlunar.space/docs/specification.gmi> seems
silent about IDN (Internationalized Domain Names, domains in Unicode,
see RFC 5890). The spec mentions URI (not 3986) but not IRI
(Internationalized Resource Identifiers, RFC 3987).

Therefore, it is not clear what servers and clients should do (send an
IRI, or accept IRI but convert it to URI or something else). A test
with some clients seem to indicate it does not work (tested at
<gemini://gémeaux.bortzmeyer.org/>):

* Amfora claims the domain name does not exist (it does exist),
"Failed to connect to the server: dial tcp: lookup
gémeaux.bortzmeyer.org: no such host."

* AV-98 does not protest and sends the IRI but the server I use
(Gemserv) fails to match either using the UTF-8 form (U-label) or the
Punycode one (A-label),

- Bombadillo says "Found "é", expected EOF"

What is the normal behaviour?