Just a quick heads up that a couple of new RFCs[1][2] update RFC
5280 w.r.t. i18n support.
[1]
https://tools.ietf.org/html/rfc8398
[2]
https://tools.ietf.org/html/rfc8399
The most notable change is a new otherName type to represent
internationalised email addresses (i.e. when the local part is not
ASCII). I have filed a ticket[3] to support this in FreeIPA (no
Dogtag changes are needed). I don't think it is urgent, but
eventually someone will ask for it.
[3]
https://pagure.io/freeipa/issue/7564
Thanks,
Fraser