Re: smtpmail support of unicode passwords

[Stephen J. Turnbull]

Harald Hanche-Olsen writes:

 > Poking around a little more in RFC4616, I see a reference to SASLprep
 > (RFC 4013) and StringPrep (RFC 3454). Apparently, the correct
 > normalization is NFKC; however, that is considered optional,

No, it's not.  RFC 4013, sec. 2.2, uses SHALL, RFC 4616, sec. 2, uses
RECOMMENDED, and RFC 4954, sec. 4 uses SHOULD (with a prospective
upgrade to MUST).  So technically, you can use something else, but
you'd better have a REALLY GOOD (in the RFC 2119 sense ;-) reason.

But it's not Emacs's problem:

 > reading between the lines a bit, I think this normalization, if done
 > at allo, is intended to happen in the server – just prior to computing
 > the hash.

As usual the RFCs leave rather wide discretion to the implementers.
But in the case of SMTP I think it would be insane for servers to fail
to normalize.