On Tue, 2007-09-11 at 19:51 +0100, Dave Cridland wrote: > If I ruled the world, I'd mandate TLS+SCRAM, and have a SHOULD for > TLS+YAP (the latter being plaintext-equiv on the server, but only a > single round-trip, so great for mobiles).
You may be missing the most popular reason for sending plain-text passwords to the server (over TLS, one hopes): it's the only way for the server to check the password against an external verifier such as an LDAP server, AD controller, or Kerberos KDC. (GSSAPI krb5 auth is much better if you have an AD controller or Kerberos KDC, of course, but I don't hold out much hope for that being universally implemented in clients.)
